Subsonic - Subsonic is a free, web-based media streamer, providing ubiquitous access to your music and video.
Spotify - Map shows when two people play same song at same time
CherryMusic - A music streaming server written in python:Stream your own music collection to all your devices!
Last.fm - The world's largest online music service. Listen online, find out more about your favourite artists, and get music recommendations, only at Last.fm
Ampache - Web ( HTTP centralized ) based audio/video streaming application
SoundCloud - Enjoy music & follow favourite artists