This is just great: NCSA Mosaic on GitHub at http://github.com/alandipert/ncsa-mosaic.

img http://img.skitch.com/20100308-pw11fgabs4ukqf89c29dy6wipn.png http://github.com/alandipert/ncsa-mosaic

This now joins the Quake source as one of my favorite old school projects.

(Hat tip flangy)