Music For Makers - Licensing good music has never been this easy.
Meetup - Helps groups of people with shared interests plan events and facilitates off line group meetings in various localities around the world.
TunePocket - Download 11,000+ royalty free music tracks and sound FX. Buy once, use forever. New music added daily. Save over 50% compared to most popular similar services. Incredible value!
Eventbrite - Discover Great Events or Create Your Own & Sell Tickets
Incompetech - Royalty Free and Creative Commons Music Archive
Bigtent - BigTent is a web-based organization and communication portal for groups.