We are running a beta version of a scalable homeserver (hosting service) right now. Some people have experimented with running their own, but i doubt anyone else is offering hosting yet.
You could try running one and let us know any bugs you encounter.
In a few months we will also release a personal homeserver that anyone can run (not for scaled hosting services).
You could also make any homeserver paradigm you want on your own. The protocol is modular and open.