I've been developing during the last weeks a DataChannel polyfill from the specs using a WebSockects based proxy server. It's far from perfect, but it's API compatible and since it's main purposse is to allow to experiment with the API until we have some native implementation, it works :-D You can find it at https://github.com/piranna/DataChannel-polyfill, and on the test folder you can find a simple test showing how it works (it's based on webrtc.io demo code, only that the video code is removed and it's adapted so it's easy to integrate with my ShareIt! project (https://github.com/piranna/ShareIt)).
Thank you for your comments! :-D I have just finished some minutes ago to remove the '_datachannel' array from the polyfill to the client code so it's now fully standard and fixed some bugs, and also added a minimal test that also works as example code for the API :-) Currently it's working on Chromium >= 21 since it has the PeerConnection object but don't the DataChannel API (that's the reason i build it), on Firefox there are more problems since it's only implemented the getUserMedia API and all the WebRTC work is being done at once on a different branch (v18a 'alder') and it's more difficult to test it, i'll give it another try now that i have the test working :-)
It seems Chrome v24 Dev and Firefox 18 Aurora support DataChannels natively (although personally I didn't be able to make them work...). Is there any "private" improvement here? Are you still busy? Can I help you in anything? :-)
Any updates on this?
I created a $50 bounty for someone fixing this.
I think you should have a look to https://github.com/feross/webtorrent
If not KadOH, who then? WebRTC could bring a lot of life to the project. It's the first time that KadOH can actually be really P2P without XMPP relays in the network, etc.