MilkDrop - 3D audio visualization plugin, compatible with WinAmp plugin API
Google Music Lab - Interactive experiments that use the Web Audio API
projectM - projectM is an LGPL'ed reimplementation of Milkdrop under OpenGL.
YuMe - A multi-screen video advertising company providing digital video brand advertising solutions.
Magic Music Visuals - Fully-customizable and highly responsive visuals for live and recorded audio & MIDI.
Cheese Posties - Ready-to-grill cheese sandwiches in the mail