Working with all kinds books, I often need inspiration for a set of sectioning styles that are coherent, logical and aesthetically appealing. Well-known examples include Edward Tufte and the style used in Robert Bringhurst's The Elements of Typographic Style.
I would kindly like to ask you to show your examples—all the better if the example includes LaTeX source. If you refer to a specific author or publication, it would be useful to include an image.
The mentioned examples are typically limited to chapter title, section and subsection. At times, I need a set of styles with more depth—chapter title, section, subsection, subsubsection, paragraph, subparagraph, etc. So sets with more depth are greatly appreciated.