Openwhyd - Collect and Share the tracks you love.
Spotify - Map shows when two people play same song at same time
Music Smasher - Find any song. Music Smasher searches Spotify, Rdio, SoundCloud, Bandcamp, and YouTube.
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
Qobuz - Qobuz for MAC/PC. Listening to Qobuz on your computer ? Enjoy all your music in the best possible conditions with our application for both Mac and Windows computers.
SoundCloud - Enjoy music & follow favourite artists