Vamo - Build your own adventure
Meetup - Helps groups of people with shared interests plan events and facilitates off line group meetings in various localities around the world.
Airfordable - Payment plans for flights before your departure.
Facebook Local - Discover places to go and events happening near you
#PriceMyTrip by Vamo - Plan a complex trip with one simple tweet
Eventbrite - Discover Great Events or Create Your Own & Sell Tickets