Youtube-DJ - Mix YouTube songs together
Momixa - Pick two songs and get the perfect mix
Edjing - Discover edjing and edjing Pro, the most powerful DJ apps for music lovers! Mix on Android, Windows and iOS devices and record then share your DJ sets!
Liveset Database - Database site with tracklists from Dj sets
YOU.DJ - Mix SoundCloud music and Youtube videos live in your browser.
FIEND.fm - "Hot or Not" for music discovery: 2 hrs of tracks in 2 mins