projectM - projectM is an LGPL'ed reimplementation of Milkdrop under OpenGL.
The Y Combinator Database - The definitive database of YC companies with all the metrics
Magic Music Visuals - Fully-customizable and highly responsive visuals for live and recorded audio & MIDI.
Startup School - How to start a startup, by Y Combinator
Kauna - Kauna is a music visualizer. Kauna renders any sound reproduction in system.
Y Combinator Companies - Interactive list of all 1000+ YC companies