Airsonic
Free and Open Source community driven media server
...You can stream to multiple players simultaneously, for instance to one player in your kitchen and another in your living room. Airsonic is designed to handle very large music collections (hundreds of gigabytes). Although optimized for MP3 streaming, it works for any audio or video format that can stream over HTTP, for instance AAC and OGG. By using transcoder plug-ins, Airsonic supports on-the-fly conversion and streaming of virtually any audio format, including WMA, FLAC, APE, Musepack, WavPack and Shorten. If you have constrained bandwidth, you may set an upper limit for the bit rate of the music streams. ...