I immediately thought of Bitcoin when reading the OP. It can, and has been "hard" forked via miner consensus. That is, of course, one level removed from git, bu

I immediately thought of Bitcoin when reading the OP. It can, and has been "hard" forked via miner consensus. That is, of course, one level removed from git, but I guess git"hub" could be more like gittorrent or something where instead of hosting a repo on one central server, the repo is hosted by a swarm and the version with the most seeds is the winner.