The texlive package database has a one line description of each (texlive) package, derived I think from the ctan catalogue.
$ pwd
/usr/local/texlive/2014/tlpkg
for i in `grep -l '\.cls' tlpobj/* ` ;do echo "";grep "^\(name\|shortdesc\| *texmf-dist.*\.cls\)" $i| sed -e "s@texmf.*/@@" ; done > cls.txt
produces a file with 588 */.cls references that looks like
a0poster
Support for designing posters on large paper.
a0poster.cls
aastex
Macros for Manuscript Preparation for AAS Journals.
aastex.cls
abntex2
Typeset technical and scientific Brazilian documents based on ABNT rules.
abntex2.cls
achemso
Support for American Chemical Society journal submissions.
achemso.cls
acmconf
Class for ACM conference proceedings.
acmconf.cls
active-conf
Class for typesetting ACTIVE conference papers.
active-conf.cls
adfathesis
Australian Defence Force Academy thesis format.
adfathesis.cls
afparticle
Typesetting articles for Archives of Forensic Psychology
afparticle.cls
afthesis
Air Force Institute of Technology thesis class.
afthesis.cls
aguplus
Styles for American Geophysical Union.
aguplus.cls
aiaa
Typeset AIAA conference papers.
aiaa-tc.cls
akktex
A collection of packages and classes.
akklecture.cls
akkscript.cls
akktecdoc.cls
akletter
Comprehensive letter support.
akletter.cls
myletter.cls
ametsoc
Official American Meteorological Society Latex Template.
ametsoc.cls
amscls
AMS document classes for LaTeX.
amsart.cls
amsbook.cls
amsdtx.cls
amsldoc.cls
amsproc.cls
aomart
Typeset articles for the Annals of Mathematics.
aomart.cls
apa
American Psychological Association format.
apa.cls
apa6
Format documents in APA style (6th edition).
apa6.cls
apa6e
Format manuscripts to APA 6th edition guidelines.
apa6e.cls
arabtex
Macros and fonts for typesetting Arabic.
arabart.cls
arabbook.cls
arabrep.cls
arabrep1.cls
articleingud
LaTeX class for articles published in INGENIERIA review.
articleingud.cls
asaetr
Transactions of the ASAE.
asaetr.cls
ascelike
Bibliography style for the ASCE.
ascelike.cls
assignment
A class file for typesetting homework and lab assignments
assignment.cls
bangorcsthesis
Typeset a thesis at Bangor University.
bangorcsthesis.cls
bangtex
Writing Bangla and Assamese with LaTeX.
barticle.cls
bbook.cls
bletter.cls
bankstatement
A LaTeX class for bank statements based on csv data.
bankstatement.cls
basque-book
Class for book-type documents written in Basque.
basque-book.cls
beamer
A LaTeX class for producing presentations and slides.
beamer.cls
beamer-FUBerlin
Beamer, using the style of FU Berlin.
FUbeamer.cls
bgteubner
Class for producing books for the publisher "Teubner Verlag".
bgteubner.cls
bhcexam
An exam class designed for Mathematics Teachers in China.
BHCexam.cls
biblatex-musuos
A biblatex style for citations in musuos.cls.
bidi
Bidirectional typesetting in plain TeX and LaTeX, using XeTeX engine.
bidimoderncv.cls
biditufte-book.cls
biditufte-handout.cls
bidipresentation
Experimental bidi presentation.
bidipresentation.cls
bookcover
A class for book covers and dust jackets.
bookcover.cls
bookest
Extended book class.
bookest.cls
brandeis-dissertation
Class for Brandeis University dissertations.
brandeis-dissertation.cls
bxjscls
Document classes based on jsclasses.
bxjsarticle.cls
bxjsreport.cls
cascadilla
Typeset papers conforming to the stylesheet of the Cascadilla Proceedings Project.
cascadilla.cls
cd
Typeset CD covers.
cd.cls
cd-cover
Typeset CD covers.
cd-cover.cls
cdpbundl
Business letters in the Italian style.
articoletteracdp.cls
letteracdp.cls
chbibref
Change the Bibliography/References title.
chletter
Class for typesetting letters to Swiss rules.
chletter.cls
cnbwp
Typeset working papers of the Czech National Bank.
cnbwp.cls
cnltx
LaTeX tools and documenting facilities.
cnltx-doc.cls
codedoc
LaTeX code and documentation in LaTeX-format file.
codedoc.cls
combine
Bundle individual documents into a single document.
combine.cls
computational-complexity
Class for the journal Computational Complexity.
cc.cls
concepts
Keeping track of formal 'concepts' for a particular field.
packagedoc.cls
concprog
Concert programmes.
ConcProg.cls
confproc
A set of tools for generating conference proceedings.
confproc.cls
contracard
Generate calling cards for dances.
contracard.cls
courseoutline
Prepare university course outlines.
courseoutline.cls
coursepaper
Prepare university course papers.
coursepaper.cls
csbulletin
LaTeX class for articles submitted to the CSTUG Bulletin (Zpravodaj).
csbulletin.cls
ctex
LaTeX classes and packages for Chinese typesetting.
ctexartutf8.cls
ctexbookutf8.cls
ctexreputf8.cls
ctexart.cls
ctexbook.cls
ctexrep.cls
curve
A class for making curriculum vitae.
curve.cls
cv4tw
LaTeX CV class, with extended details.
cv4tw.cls
cweb-latex
A LaTeX version of CWEB.
cweb-hy.cls
cweb.cls
dccpaper
Typeset papers for the International Journal of Digital Curation
idcc.cls
ijdc-v9.cls
dcpic
Commutative diagrams in a LaTeX and TeX documents.
europroc.cls
dickimaw
Books and tutorials from the "Dickimaw LaTeX Series".
novices.cls
dickimawthesis.cls
dinbrief
German letter DIN style.
dinbrief.cls
disser
Class and templates for typesetting dissertations in Russian.
disser.cls
gost732.cls
dithesis
dithesis.cls
droit-fr
Document class and bibliographic style for French law.
droit-fr.cls
dtk
Document class for the journal of DANTE.
dtk.cls
dvdcoll
A class for typesetting DVD archives
dvdcoll.cls
ebsthesis
Typesetting theses for economics
ebsthesis.cls
economic
BibTeX support for submitting to Economics journals.
agecon.cls
ajae.cls
apecon.cls
ecca.cls
erae.cls
itaxpf.cls
jrurstud.cls
njf.cls
oegatb.cls
pocoec.cls
regstud.cls
worlddev.cls
ecv
A fancy Curriculum Vitae class.
ecv.cls
einfuehrung
Examples from the book Einfuhrung in LaTeX.
beispiel.cls
bspcalweekly.cls
bspdvdcoll.cls
bspfont.cls
bsppstricks.cls
exaarticle.cls
exaarticle2.cls
exaartplain.cls
exabeamer.cls
exabook.cls
exabook2.cls
exadante.cls
exafoils.cls
exafubeamer.cls
exafupd.cls
examargin.cls
examemoir.cls
examinimal-mathsymbols.cls
examinimal.cls
exapd.cls
exaprosper.cls
exareport.cls
exaseminar.cls
exaslidenotes.cls
exasymbol.cls
exaxetex.cls
screxa.cls
screxabook.cls
screxareport.cls
ejpecp
Class for EJP and ECP.
ejpecp.cls
elbioimp
A LaTeX document class for the Journal of Electrical Bioimpedance.
elbioimp.cls
elpres
A simple class for electronic presentations
elpres.cls
elsarticle
Class for articles for submission to Elsevier journals.
elsarticle.cls
elteikthesis
Thesis class for ELTE University Informatics wing.
elteikthesis.cls
elzcards
Typeset business cards, index cards and flash cards easyly.
elzcards.cls
emulateapj
Produce output similar to that of APJ.
emulateapj.cls
erdc
Style for Reports by US Army Corps of Engineers.
erdc.cls
eskd
Modern Russian typesetting.
eskd.cls
eskdx
Modern Russian typesetting.
eskdgraph.cls.in
eskdtab.cls.in
eskdtext.cls.in
eskdgraph.cls
eskdtab.cls
eskdtext.cls
estcpmm
Style for Munitions Management Project Reports.
estcpmm.cls
europasscv
Unofficial class for the new version of the Europass curriculum vitae
europasscv.cls
europecv
Unofficial class for European curricula vitae.
europecv.cls
exam
Package for typesetting exam scripts.
exam.cls
examdesign
LaTeX class for typesetting exams.
examdesign.cls
exam-n
Exam class, focused on collaborative authoring.
exam-n.cls
exam-n.cls
excludeonly
Prevent files being \include-ed.
extsizes
Extend the standard classes' size options.
extarticle.cls
extbook.cls
extletter.cls
extproc.cls
extreport.cls
facsimile
Document class for preparing faxes.
facsimile.cls
factura
Typeset and calculate invoices according to Venezuela law.
factura.cls
facture
Generate an invoice.
facture.cls
fancyslides
Custom presentation class built upon LaTeX Beamer.
fancyslides.cls
FAQ-en
A compilation of Frequently Asked Questions with answers.
faq.cls
fbithesis
Computer Science thesis class for University of Dortmund.
fbithesis.cls
flacards
Generate flashcards for printing.
flacards.cls
flashcards
A class for typesetting flashcards.
flashcards.cls
frletter
Typeset letters in the French style.
frletter.cls
gaceta
A class to typeset La Gaceta de la RSME.
gaceta.cls
gatech-thesis
Georgia Institute of Technology thesis class
gatech-thesis.cls
g-brief
Letter document class.
g-brief.cls
g-brief2.cls
gmdoc
Documentation of LaTeX packages.
gmdocc.cls
gsemthesis
Geneva School of Economics and Management PhD thesis format.
gsemthesis.cls
guide-to-latex
mpletter.cls
harnon-cv
A CV document class with a vertical timeline for experience.
harnon-cv.cls
hausarbeit-jura
Class for writing "juristiche Hausarbeiten" at German Universities.
hausarbeit-jura.cls
hc
Replacement for the LaTeX classes.
hcart.cls
hcletter.cls
hcreport.cls
hcslides.cls
hepthesis
A class for academic reports, especially PhD theses.
hepthesis.cls
hitec
Class for documentation.
hitec.cls
hletter
Flexible letter typesetting with flexible page headings.
hletter.cls
hpsdiss
A dissertation class.
hpsdiss.cls
hrlatex
LaTeX support for Croatian documents.
fsbispit.cls
icsv
Class for typesetting articles for the ICSV conference.
icsv.cls
IEEEconf
Macros for IEEE conference proceedings.
IEEEconf.cls
IEEEtran
Document class for IEEE Transactions journals and conferences.
IEEEtran.cls
ijmart
LaTeX Class for the Israel Journal of Mathematics.
ijmart.cls
image-gallery
Create an overview of pictures from a digital camera or from other sources.
image-gallery.cls
imsproc
Typeset IMS conference proceedings.
imsproc.cls
imtekda
IMTEK thesis class.
IMTEKda.cls
iso
Generic ISO standards typesetting macros.
isov2.cls
isodoc
A LaTeX class for typesetting letters and invoices.
isodoc.cls
iwhdp
Halle Institute for Economic Research (IWH) Discussion Papers.
iwhdp.cls
jmlr
Class files for the Journal of Machine Learning Research.
jmlr.cls
jmlrbook.cls
jpsj
Document Class for Journal of the Physical Society of Japan.
jpsj2.cls
jsclasses
Classes tailored for use with Japanese.
jsarticle.cls
jsbook.cls
jspf.cls
kiyou.cls
jura
A document class for German legal texts.
jura.cls
juramisc
Typesetting German juridical documents.
jurabook.cls
juraovw.cls
juraurtl.cls
kdgdocs
Document classes for Karel de Grote University College.
kdgcoursetext.cls
kdgmasterthesis.cls
kerntest
Print tables and generate control files to adjust kernings.
kerntest.cls
kluwer
kluwer.cls
knittingpattern
Create knitting patterns.
knittingpattern.cls
komacv
Typesetting a beuatiful CV with various style options.
komacv.cls
koma-script
A bundle of versatile classes and packages
scrguide.cls
scrartcl.cls
scrbook.cls
scrdoc.cls
scrlttr2.cls
scrreprt.cls
kotex-oblivoir
A LaTeX document class for typesetting Korean documents.
oblivoir-base.cls
oblivoir-xlua.cls
oblivoir.cls
xoblivoir.cls
kpfonts
A complete set of fonts for text and mathematics.
christophe.cls
l3kernel
LaTeX3 programming conventions.
l3doc.cls
labbook
Typeset laboratory journals.
labbook.cls
latex
A TeX macro package that defines LaTeX.
article.cls
book.cls
letter.cls
ltnews.cls
ltxdoc.cls
ltxguide.cls
minimal.cls
proc.cls
report.cls
slides.cls
latexfileversion
Prints the version and date of a LaTeX class or style file.
latex-graphics-companion
Examples from The LaTeX Graphics Companion.
ppex.cls
latexindent
Indent a LaTeX document, highlighting the programming structure.
testcls.cls
latex-referenz
Examples from the book "LaTeX Referenz".
bspfont.cls
exaarticle.cls
exaarticle2.cls
exabook.cls
exabook2.cls
examinimal.cls
exareport.cls
exaxetex.cls
screxa.cls
screxabook.cls
screxareport.cls
latex-tds
A structured copy of the LaTeX distribution.
tools-overview.cls
leaflet
Create small handouts (flyers).
leaflet.cls
lettre
Letters and faxes in French.
lettre.cls
limap
Typeset maps and blocks according to the Information Mapping method.
limap.cls
lps
Class for "Logic and Philosophy of Science".
lps.cls
lt3graph
Provide a graph datastructure for experimental LaTeX3.
lt3graph-packagedoc.cls
ltxdockit
Documentation support.
ltxdockit.cls
ltxmisc
Miscellaneous LaTeX packages, etc.
abstbook.cls
beletter.cls
flashcard.cls
iagproc.cls
luaintro
Examples from the book "Einfuhrung in LuaTeX und LuaLaTeX".
beispiel.cls
bspcalweekly.cls
bspdvdcoll.cls
bspfont.cls
bsppstricks.cls
exaarticle.cls
exaarticle2.cls
exaartplain.cls
exabeamer.cls
exabook.cls
exabook2.cls
exadante.cls
exafoils.cls
exafubeamer.cls
exafupd.cls
examargin.cls
examemoir.cls
examinimal-mathsymbols.cls
examinimal.cls
exapd.cls
exaprosper.cls
exareport.cls
exaseminar.cls
exaslidenotes.cls
exasymbol.cls
exaxetex.cls
screxa.cls
screxabook.cls
screxareport.cls
lualatex-doc
A guide to use of LaTeX with LuaTeX.
lltxdoc.cls
luatexja
Typeset Japanese with lua(la)tex.
ltjarticle.cls
ltjbook.cls
ltjltxdoc.cls
ltjreport.cls
ltjsarticle.cls
ltjsbook.cls
ltjskiyou.cls
ltjspf.cls
mafr
Mathematics in accord with French usage.
cours.cls
fiche.cls
matc3mem
Class for MatematicaC3 textbooks.
matc3mem.cls
math-e
Examples from the book Typesetting Mathematics with LaTeX.
exaarticle.cls
exaarticle2.cls
exaartplain.cls
exareport.cls
exasymbol.cls
mcmthesis
Template designed for MCM/ICM
mcmthesis.cls
mdframed
Framed environments that can split at page boundaries.
ltxmdf.cls
meetingmins
Format written minutes of meetings.
meetingmins.cls
memoir
Typeset fiction, non-fiction and mathematical books.
memoir.cls
mentis
A basis for books to be published by Mentis publishers.
mentis.cls
mil3
Samples from Math into LaTeX, third edition.
svsing6.cls
moderncv
A modern curriculum vitae class.
moderncv.cls
msu-thesis
Class for Michigan State University Master's and PhD theses.
msu-thesis.cls
mugsthesis
Thesis class complying with Marquette University Graduate School requirements.
mugsthesis.cls
musuos
Typeset papers for the department of music, Osnabruck.
musuos.cls
muthesis
Classes for University of Manchester Dept of Computer Science.
muthesis.cls
third-rep.cls
mwcls
Polish-oriented document classes.
mwart.cls
mwbk.cls
mwrep.cls
mycv
A list-driven CV class, allowing TikZ decorations.
mycv.cls
nature
Prepare papers for the journal Nature.
nature.cls
ncclatex
An extended general-purpose class
ncc.cls
nccproc.cls
sibjnm.cls
nddiss
Notre Dame Dissertation format class.
nddiss2e.cls
ndsu-thesis
North Dakota State University disquisition class.
ndsu-thesis.cls
newlfm
Write letters, facsimiles, and memos.
newlfm.cls
nih
A class for NIH grant applications.
nih.cls
nlctdoc
Package documentation class.
nlctdoc.cls
noindentafter
Tool to prevent paragraph indentation after environments/macros.
noindentafter-packagedoc.cls
nostarch
LaTeX class for No Starch Press.
nostarch.cls
nrc
Class for the NRC technical journals.
nrc1.cls
nrc2.cls
ntgclass
"European" versions of standard classes.
artikel1.cls
artikel2.cls
artikel3.cls
boek.cls
boek3.cls
brief.cls
rapport1.cls
rapport3.cls
octavo
Typeset books following classical design and layout.
octavo.cls
onrannual
Class for Office of Naval Research Ocean Battlespace Sensing annual report.
onrannual.cls
paper
Versions of article class, tuned for scholarly publications.
journal.cls
paper.cls
papertex
Class for newspapers, etc.
papertex.cls
pbsheet
Problem sheet class.
pbsheet.cls
pbsheet.cls
pecha
Print Tibetan text in the classic pecha layout style.
pecha.cls
petiteannonce
A class for small advertisements.
petiteannonce.cls
philosophersimprint
Typesetting articles for "Philosophers' Imprint".
philosophersimprint.cls
pinlabel
A TeX labelling package.
gtpart.cls
pittetd
Electronic Theses and Dissertations at Pitt.
pittetd.cls
pkgloader
Managing the options and loading order of other packages.
pkgloader-packagedoc.cls
pkuthss
LaTeX template for dissertations in Peking University.
pkuthss.cls
plari
Typesetting stageplay scripts.
plari.cls
play
Typeset drama using LaTeX.
play.cls
postcards
Facilitates mass-mailing of postcards (junkmail).
postcards.cls
powerdot
A presentation class.
powerdot.cls
powerdot-FUBerlin
Powerdot, using the style of FU Berlin.
FUpowerdot.cls
ppr-prv
Prosper preview.
ppr-prv.cls
pracjourn
Typeset articles for PracTeX.
pracjourn.cls
presentations-en
Examples from the book Presentations with LaTeX.
beispiel.cls
bspcalweekly.cls
bspdvdcoll.cls
bspfont.cls
bsppstricks.cls
exaarticle.cls
exaarticle2.cls
exaartplain.cls
exabeamer.cls
exabook.cls
exabook2.cls
exadante.cls
exafoils.cls
exafubeamer.cls
exafupd.cls
examargin.cls
examemoir.cls
examinimal-mathsymbols.cls
examinimal.cls
exapd.cls
exaprosper.cls
exareport.cls
exaseminar.cls
exaslidenotes.cls
exasymbol.cls
exaxetex.cls
prosper.cls
screxa.cls
screxabook.cls
screxareport.cls
slidenotes.cls
pressrelease
A class for typesetting press releases.
pressrelease.cls
proposal
A class for preparing proposals.
proposal.cls
reporting.cls
dfgproposal.cls
dfgreporting.cls
euproposal.cls
eureporting.cls
prosper
LaTeX class for high quality slides.
prosper.cls
protocol
A class for minutes of meetings.
protocol.cls
przechlewski-book
Examples from Przechlewski's LaTeX book.
upmgr.cls
wkmgr.cls
pstricks
PostScript macros for TeX.
pst-doc.cls
pstricks-examples
PSTricks examples.
beispiel.cls
bspcalweekly.cls
bspdvdcoll.cls
bspfont.cls
bsppstricks.cls
exaarticle.cls
exaarticle2.cls
exaartplain.cls
exabeamer.cls
exabook.cls
exafoils.cls
exafubeamer.cls
exafupd.cls
examargin.cls
examinimal.cls
exapd.cls
exaprosper.cls
exareport.cls
exaseminar.cls
exaslidenotes.cls
exasymbol.cls
exaxetex.cls
screxa.cls
screxabook.cls
screxareport.cls
ptex
A TeX system for publishing in Japanese.
jarticle.cls
jbook.cls
jltxdoc.cls
jreport.cls
plnews.cls
tarticle.cls
tbook.cls
treport.cls
ptptex
Macros for 'Progress of Theoretical Physics'.
ptptex.cls
qcm
A LaTeX2e class for making multiple choice questionnaires
qcm.cls
recipe
A LaTeX class to typeset recipes.
recipe.cls
recipecard
Typeset recipes in note-card-sized boxes.
recipecard.cls
refman
Format technical reference manuals.
refart.cls
refrep.cls
resphilosophica
Typeset articles for the journal Res Philosophica.
resphilosophica.cls
resumecls
Typeset a resumee in both Chinese and English.
resumecls.cls
revtex
Styles for various Physics Journals.
revtex4-1.cls
revtex4
revtex4.cls
rtklage
A package for German lawyers
rtklage.cls
ryethesis
Class for Ryerson Unversity Graduate School requirements.
ryethesis.cls
sageep
Format papers for the annual meeting of EEGS.
sageep.cls
sapthesis
Typeset theses for Sapienza-University, Rome.
sapthesis.cls
schule
Support for teachers at German schools.
schuleab.cls
schulein.cls
schuleit.cls
schulekl.cls
schuleub.cls
schuleue.cls
schullsg.cls
schullzk.cls
schwalbe-chess
Typeset the German chess magazine "Die Schwalbe"
schwalbe.cls
sciposter
Make posters of ISO A3 size and larger.
sciposter.cls
screenplay
A class file to typeset screenplays.
screenplay.cls
scrjrnl
Typeset diaries or journals.
scrjrnl.cls
sduthesis
Thesis Template of Shandong University
sduthesis.cls
seminar
Make overhead slides.
seminar.cls
sesamanuel
Class and package for sesamath books or paper
sesamanuel.cls
seuthesis
LaTeX template for theses at Southeastern University.
zharticle.cls
sffms
Typesetting science fiction/fantasy manuscripts.
sffms.cls
shipunov
A collection of LaTeX packages and classes.
cassete.cls
etiketka.cls
sidenotes
Typeset notes containing rich content, in the margin.
caesar_book.cls
sides
A LaTeX class for typesetting stage plays.
sides.cls
simplecv
A simple class for writing curricula vitae.
simplecv.cls
simurgh
Typeset Parsi in LuaLaTeX.
simurgh-doc.cls
skb
Tools for a repository of long-living documents.
skbarticle.cls
skbbeamer.cls
skbbook.cls
skblncsbeamer.cls
skblncsppt.cls
skbmoderncv.cls
skdoc
Documentation and extraction for packages and document classes.
skdoc.cls
skeyval
Key-value parsing combining features of xkeyval and pgfkeys.
skeyval-testclass.cls
skrapport
'Simple' class for reports, etc.
skrapport.cls
sphdthesis
Latex template for writing PhD Thesis
SPhdThesis.cls
SPhdThesis.cls
spie
Support for formatting SPIE Proceedings manuscripts.
spie.cls
sr-vorl
Class for Springer books.
sr-vorl.cls
sslides
Slides with headers and footers.
sslides.cls
stage
A LaTeX class for stage plays
stage.cls
standalone
Compile TeX pictures stand-alone or as part of a document.
standalone.cls
stellenbosch
Stellenbosch thesis bundle.
usthesis.cls
stex
An Infrastructure for Semantic Preloading of LaTeX Documents.
cnx.cls
cnx.cls.ltxml
hwexam.cls
hwexam.cls.ltxml
mikoslides.cls
mikoslides.cls.ltxml
omdoc.cls
omdoc.cls.ltxml
subfiles
Individual typesetting of subfiles of a "main" document.
subfiles.cls
suftesi
A document class for typesetting theses, books and articles.
suftesi.cls
sugconf
SAS(R) user group conference proceedings document class.
sugconf.cls
tabriz-thesis
A template for the University of Tabriz.
tabriz-thesis.cls
talk
A LaTeX class for presentations.
talk.cls
tcldoc
Doc/docstrip for tcl.
tcldoc.cls
tclldoc.cls
tds
The TeX Directory Structure standard.
tdsguide.cls
templates-fenn
Templates for TeX usage.
texpower
Create dynamic online presentations with LaTeX.
powersem.cls
texworks
Cross-platform friendly front end.
thesis-ekf
Thesis class for Eszterhazy Karoly College.
thesis-ekf.cls
thuthesis
Thesis template for Tsinghua University.
thuthesis.cls
tikzposter
Create scientific posters using TikZ.
tikzposter.cls
tkz-doc
Documentation macros for the TKZ series of packages.
tkz-doc.cls
tlc2
Examples from "The LaTeX Companion", second edition.
ttctexa.cls
ttctexamargin.cls
ttctexareport.cls
toptesi
Bundle for typesetting multilanguage theses.
toptesi.cls
tudscr
Typeset documents in the corporate style of TU Dresden.
tudscrartcl.cls
tudscrbook.cls
tudscrdoc.cls
tudscrman.cls
tudscrreprt.cls
tufte-latex
Document classes inspired by the work of Edward Tufte.
tufte-book.cls
tufte-handout.cls
tufte-book.cls
tufte-handout.cls
tugboat
LaTeX macros for TUGboat articles.
ltugboat.cls
ltugproc.cls
tui
Thesis style for the University of the Andes, Colombia.
tui.cls
turabian
Create Turabian-formatted material using LaTeX.
turabian.cls
turabian-formatting
Formatting based on Turabian's Manual.
turabian-researchpaper.cls
turabian-thesis.cls
uaclasses
University of Arizona thesis and dissertation format.
my-thesis.cls
ua-thesis.cls
uadocs
Course texts and masters theses in University of Antwerp style.
uacoursetext.cls
uamasterthesis.cls
uafthesis
Document class for theses at University of Alaska Fairbanks.
uafthesis.cls
ucbthesis
ucbthesis.cls
ucdavisthesis
A thesis/dissertation class for University of California at Davis.
ucdavisthesis.cls
ucthesis
University of California thesis format.
ucthesis.cls
udesoftec
Thesis class for the University of Duisburg-Essen.
udesoftec.cls
uebungsblatt
A LaTeX class for writing exercise sheets.
uebungsblatt.cls
uestcthesis
Thesis class for UESTC
uestcthesis.cls
uiucredborder
Class for UIUC thesis red-bordered forms.
uiucredborder.cls
uiucthesis
UIUC thesis class.
uiucthesis.cls
ulthese
Thesis class and templates for Universite Laval.
ulthese.cls
umich-thesis
University of Michigan Thesis LaTeX class.
umich-thesis.cls
umthesis
Dissertations at the University of Michigan.
umthesis.cls
unamth-template
UNAM Thesis LaTeX Template
PhDthesisPSnPDF.cls
PhDthesisPSnPDF.cls.bak
underoverlap
Position decorations over and under expressions.
packagedoc.cls
uothesis
Class for dissertations and theses at the University of Oregon.
uothesis.cls
uowthesis
Document class for dissertations at the University of Wollongong.
UoWthesis.cls
upmethodology
Writing specifications such as for UP-based methodologies.
upmethodology-document.cls
uptex
Unicode version of pTeX.
ujarticle.cls
ujbook.cls
ujreport.cls
utarticle.cls
utbook.cls
utreport.cls
urcls
Beamer and scrlttr2 classes and styles for the University of Regensburg.
URbeamer.cls
URletter.cls
uspatent
U.S. Patent Application Tools for LaTeX and LyX.
uspatent.cls
ut-thesis
University of Toronto thesis style.
ut-thesis.cls
uwmslide
Slides with a simple Power Point like appearance.
uwmslide.cls
uwthesis
University of Washington thesis class.
uwthesis.cls
vntex
Support for Vietnamese.
vnsample.cls
withargs
Ephemeral macro use.
withargs-packagedoc.cls
wsemclassic
LaTeX class for Bavarian school w-seminar papers.
wsemclassic.cls
xepersian
Persian for LaTeX, using XeTeX.
xepersian-magazine.cls
xkeyval
Extension of the keyval package.
xkveca.cls
xkvecb.cls
xypic
Flexible diagramming macros.
movie.cls
yathesis
yathesis provides a LaTeX class that aims to help to write a thesis following French rules
yathesis.cls
ydoc
Macros for documentation of LaTeX classes and packages.
ydoc.cls
york-thesis
A thesis class file for York University, Toronto.
york-thesis.cls
ack '\.cls$' $(kpsewhich -a ls-R) | wc -l
gives 577. A comprehensive comparison would take quite a long time.ack
...?grep -c '\.cls$' /usr/local/texlive/2014/texmf-dist/ls-R
produces574
(I have three classes in TEXMFLOCAL).