Is there an application for online, real-time, collaborative interior design?

I’ve not played an MMO (massively multi-player online) game, but I understand that in such a game you can play against several opponents online, in real time, with each one of you sitting in your own homes (or offices!).

Now I’m imagining something like that but for interior design, where you, your interior designer, your contractor, and one or more friends can work together online, in real time, on a remodel, a piece of furniture, or even a complete interior design. Does such an application exist?

About year ago, I looked at Google Sketchup, and it just didn’t cut it.