SOUNDS - Discover music with friends
Kibii - Discover exciting things to do!
Wohooo.net - Create Your Own Online Radio Station
Rally by Eventbrite - Find the best local events and rally your friends to join
Listen2MyRadio - Stop dreaming, start streaming. Free and premium Shoutcast and Icecast audio broadcasting.
Party with a Local - Party with a Local is a free app that connects travelers with locals that want to party.