L Server software which controls a wide range of Squeezebox/Slim Devices audio players and compatible hardware (formerly Logitech Media Server).
N Modern Music Server and Streamer, compatible with Subsonic/Airsonic.
Personal music streaming server that works.
Music library manager and MusicBrainz tagger (command-line and Web interface).
A Audiobook and podcast server. It streams all audio formats, keeps and syncs progress across devices. Comes with open-source apps for Android and iOS.
M Extensible music server. Offers a superset of the mpd API, as well as integration with 3rd party services like Spotify, SoundCloud etc.
Synchronous multiroom audio server.