Wacht.tv - Reddit meets MTV, discover music videos!
Momixa - Pick two songs and get the perfect mix
DiscoverWeekly.dev - The playlists made by devs, every Wednesday
Liveset Database - Database site with tracklists from Dj sets
SameTunes - Music social network to compare, share, and discover music.
FIEND.fm - "Hot or Not" for music discovery: 2 hrs of tracks in 2 mins