Bliss music library is a multithreaded C library used to compute distance
between songs. It is especially usable through MPD with Blissify. It is can be
useful for creating "intelligent" playlists and/or continuous play, a la
Spotify/Grooveshark Radio.

Bliss is really useful when used as a plug-in for audio players.

WWW: https://github.com/Polochon-street/bliss