- Platforms: Windows XP/Vista/7/8
- License: Free software (GPL)
- Languages: en, zh, fr, es, hu, ru, nl, pl, de, it, da, cs, sl, sk, uk, tr, pt, no, sv, ca, ar, lt, gl, fi, el, ro, ko, he, fa, sgs, bg, id, sq, ja, hr, ka, eu, be, sr, nn, th, ms, oc, fur, lb, tl, uz, kk, af, ky, mk, lv, ta, az, bs, eo, lij, hi, sc, ug, te, an, si
- Unicode: Yes
- RTL/bidi: Yes
% !TEX directives: No
- Syntax Highlighting: Yes, customizable (also background color)
- Code Completion: Yes, customizable
- Code Folding: Yes
- Spell Checking: Yes (through DSpellCheck)
- SyncTeX: Yes
- Built-in Output Viewer: No. You can configure notepad++ to use an external PDF viewer like Acrobat Reader or SumatraPDF with forward and backward searching.
- Project Management: Yes (no master file)
I use Notepad++ and I love it. It has all the powerful features you expect from a good text editor (powerful find/replace, regex, macros, plugin support, etc.) and lots of features for coding, like syntax highlighting (and it has built-in rules for TeX), code folding, etc. The best part is that you can map keys to run external programs, so all you have to do is tap a bound key and it instantly runs your favorite compiler or automator and displays your output in one step, outputting errors in the command window if there are any.
It's not made exclusively for TeX, but if you're on Windows and want to use a single text editor for many purposes, one of which is TeX, Notepad++ is a very good option.
This question has answers with two methods of setting up the connection between notepad++ and a TeX distribution, as well as with SumatraPDF.