Qstn - Create and share polls and get live results
Meetup - Helps groups of people with shared interests plan events and facilitates off line group meetings in various localities around the world.
Polls API - Scalable, efficient API to build polls, quizzes, ratings and many more
Eventbrite - Discover Great Events or Create Your Own & Sell Tickets
Polls.io - Create simple polls in seconds
Bigtent - BigTent is a web-based organization and communication portal for groups.