Meetup - Helps groups of people with shared interests plan events and facilitates off line group meetings in various localities around the world.
Player.me - Player.me is the social discovery platform for the gaming community.
Eventbrite - Discover Great Events or Create Your Own & Sell Tickets
Infonaira jobs - Infonaira strives to post recent free jobs, giving job seekers free access to search for jobs.
Bigtent - BigTent is a web-based organization and communication portal for groups.
Kamcord - Live stream anything on your phone's screen