Vanilla Forums - Build an engaging community forum using Vanilla's modern cloud forum software.
Mightybell - Build a community and a business on mobile
Discourse - Discourse is an open source discussion platform built for the next decade of the Internet.
MyTalk - Build a community around your product
XenForo - Intuitive. Social. Engaging. Fast. XenForo brings a fresh outlook to forum software.
Hey.Cafe - Hey.Café is a social network built around communities called cafés.