Eventbrite - Discover Great Events or Create Your Own & Sell Tickets
Higher Logic - Private, secure online communities that stimulate conversation and ignite engagement.
Cvent - Cvent's event management software provides event planners with a complete solution to increase event attendance and decrease event costs.
Common Room - Common Room is the intelligent community growth platform that helps you deepen relationships, build better products and drive business value.
Eventzilla - Eventzilla lets you sell tickets online and manage attendees from one integrated application.
Discourse - Discourse is an open source discussion platform built for the next decade of the Internet.