Here Comes Habitat - The M.A.D.E.
http://themade.org/posts/552
At this point, we are ready to announce that we feel we have a very good chance of bringing Habitat online, in its original form, for play online with Commodore 64 emulators as the client.
Qlink Reloaded
http://www.quantumlink.tk
Someone reverse-engineered the old Quantum Link (pre-AOL) service and got both classic C64 hardware and modern emulators working with it.