projectM - projectM is an LGPL'ed reimplementation of Milkdrop under OpenGL.
VLC Media Player - VLC is a free and open source cross-platform multimedia player and framework.
Magic Music Visuals - Fully-customizable and highly responsive visuals for live and recorded audio & MIDI.
AIMP - AIMP : Free Audio Player : Официальный сайт программы
Kauna - Kauna is a music visualizer. Kauna renders any sound reproduction in system.
foobar2000 - An advanced freeware audio player for the Windows platform.