projectM - projectM is an LGPL'ed reimplementation of Milkdrop under OpenGL.
cmd.fm UI - Music visualized and controlled via a command line interface
Magic Music Visuals - Fully-customizable and highly responsive visuals for live and recorded audio & MIDI.
Graphic Foundry - High-impact audio reactive music visualizers 💎
Kauna - Kauna is a music visualizer. Kauna renders any sound reproduction in system.
SYQEL - Bring your music to life