Our winning entry for Y! HackU involves a multi-person video chat using webRTC to create a Peer-To-Peer video hangout, which works faster than any other video chat provider. It is ideal for people chatting on the same network (such as corporate & university networks).
Since this was developed over a 24 hour hackathon, the code is messy in places. The design is responsive, and should work on most devices (including mobile/tablets). It should degrade to a doc editor + chat for devices without webRTC support (which is just Chrome>=21, Firefox>=17, Opera>=12 at present). The following is the feature set we require for various features: