FIEND.fm - "Hot or Not" for music discovery: 2 hrs of tracks in 2 mins
Music Suggestions Ninja - Enter an artist's name & find similar, lesser known artists
Pacemaker - Create and share mixtapes with friends
RYSE UP - Connecting up-and-coming artists with the world's top talent
Boil the Frog - Create a seamless playlist between any two artists
Cymbal - Music discovery powered by friends