VLC Media Player - VLC is a free and open source cross-platform multimedia player and framework.
Sampulator - Make (and record) beats on your keyboard
AIMP - AIMP : Free Audio Player : Официальный сайт программы
Auxy Music Studio - Auxy brings real music creation to iPhone in a simple and inspiring format.
foobar2000 - An advanced freeware audio player for the Windows platform.
Ramsophone - A generative art/music machine. (Be sure to refresh!)