SOUNDS - Discover music with friends
Openwhyd - Collect and Share the tracks you love.
Wohooo.net - Create Your Own Online Radio Station
Music Smasher - Find any song. Music Smasher searches Spotify, Rdio, SoundCloud, Bandcamp, and YouTube.
Listen2MyRadio - Stop dreaming, start streaming. Free and premium Shoutcast and Icecast audio broadcasting.
Zoff - Collaborate on a live music and video playlist with your friends.