QWave: Qt-based waveform display and audio playback class library.
Music Server is a pure-Python MP3 "jukebox" software. The focus in on ease-of-use, reliability and extensibility. The high-level architecture is a two tier single server/multiple clients system.
Znap is a c/python network mixing daemon and music server. It can load streams supported by fmod library (ogg/mp3/wav...) and mix them together. Can be controlled via Tcp or XmlRpc. Future releases will provide playlist/db and scheduling capabilities.
minky is an mpd client written for use in my car. Essentially, minky is the information display, and uses mcandy driven shell scripts to provide UI.
pyAmpSync is a client/server addon application (written in Python) for WinAmp which allows the synchronisation of multiple WinAmp instances on networked PCs.