Discover on Demand - Just like Spotify's Discover Weekly, but whenever you want.
VLC Media Player - VLC is a free and open source cross-platform multimedia player and framework.
Rocketgraph - Rocketgraph is an open-source drop in replacement to Firebase, except it's much better.
foobar2000 - An advanced freeware audio player for the Windows platform.
Spotify - Map shows when two people play same song at same time
Winamp - Winamp is a media player that allows users to play multiple-file formats, arrange media in a varied file-management system, and play unique media with AAC encoding.