Tilt Brush - Paint in spaces around you with Virtual Reality
MilkDrop - 3D audio visualization plugin, compatible with WinAmp plugin API
A-Painter - Paint in VR in your Browser
projectM - projectM is an LGPL'ed reimplementation of Milkdrop under OpenGL.
Kodon - Kodon is the fastest-growing feature-rich VR sculpting and modeling software designed for professionals who want to do their commercial projects easily and quickly.
Magic Music Visuals - Fully-customizable and highly responsive visuals for live and recorded audio & MIDI.