projectM - projectM is an LGPL'ed reimplementation of Milkdrop under OpenGL.
Fliqlo Screensaver - A screensaver that displays the time using a flip clock.
Magic Music Visuals - Fully-customizable and highly responsive visuals for live and recorded audio & MIDI.
Padbury Clock Screensaver - Minimal screensaver for Mac
Kauna - Kauna is a music visualizer. Kauna renders any sound reproduction in system.
Clock Screen Saver - Clock Screen Saver is a free cool looking screen saver that displays the current time in the way of digital or analog clock faces.