Looks nice. I went into the tarball, looking for the Sage code snippets (they seem to be only inline in the Tex files). Then, besides the possibly redundant .hg dir, I noticed there were no image files for the figures. Those are also inline, with "{tikzpicture}"

Seems to be a fairly recent thing. Found this 2006 paper: http://www.tug.org/TUGboat/Articles/tb28-1/tb88mertz.pdf

P.S. This seems good enough to fetch all the Sage listings:

    sed -e '/begin.lstlisting/,/end.lstlisting/p' -e d *.tex

(Just in case it's handy for someone else. I always forget how 'sed' ranges work.)

P.P.S. The PGF/TikZ graphics for TeX seem to have been first released in 2005: http://sourceforge.net/projects/pgf/ . These things sneak up on you when you are not looking ... Google even tells me there's an "Inkscape extension for exporting SVG paths as TikZ code"