Mixxx - The most powerful free DJ software in the world.
Knowthelist - Knowthelist - the awesome party music player Easy to use for all party guests
Serato DJ - Serato DJ is award winning, digital DJing software used by professionals across the globe.
ServeStream - ServeStream is an open-source application that is intended for HTTP media player streaming, and the media server browser comes with the alluring support for custom online radio and Shoutcast streams.
Djay - djay gives you instant access to all your existing tracks and playlists from iTunes.
MixTape - Home of MixTape, an OSX application for creating beat matched mixes with simple export to the web or iTunes.