OBS Studio - Free and open source software for video recording and live streaming for Mac, Windows and Linux.
MilkDrop - 3D audio visualization plugin, compatible with WinAmp plugin API
HandBrake - HandBrake allows users to easily convert video files into a wide variety of different formats.
projectM - projectM is an LGPL'ed reimplementation of Milkdrop under OpenGL.
Livestream - A video live streaming platform that allows it's customers to broadcast live video content...
Magic Music Visuals - Fully-customizable and highly responsive visuals for live and recorded audio & MIDI.