Gather: We're building a virtual universe which fundamentally improves how people interact online.
Gravity: a decentralized, secure, and open social network.
CourseRoad: a 4-year academic planner for the MIT community.
DRSP: a real-time massive multiplayer decentralized virtual world. (only works in Chrome) (jk doesn't work because the last peering server is bricked in a locked-down building under a desk in Cambridge and I'm busy)