We have put together a demo using vostopia’s avatar system [[/URL] and Exit Games’ Photon Unity Networking [[/URL] to set up a multiplayer chatroom with customisable avatars that anyone can do in about ten minutes. From there, you can add content that you either create yourself or source from the asset store and have a world of your own that you can invite your friends to in very little time.
Here is a video tutorial for how to set it up:
And here is an associated blog post with a bit more detail:
http://blog.vostopia.com/2014/08/07/build-a-virtual-world-with-vostopia-avatars/
And a screenshot showing two clients running the empty world with different avatars.