Swapcard - The most intuitive platform for event organizers to engage their audiences. Connect attendees and boost exhibitors ROI like never before.
Palaround - Meet people you should be friends with.
Eventbrite - Discover Great Events or Create Your Own & Sell Tickets
Digg - Digg delivers the most interesting and talked-about stories on the Web right now.
Attendify - Develop relationships at the events that you attend by creating smaller events with just a few people.
quippd - quippd is a social news site that anyone can edit.