I've played in 6 games:
And run two:
I've put together a patch to VNC (applies to tightvnc 1.2.9 unix source) that allows people to share multiple desktops between multiple users. It improves management of who's in control of each desktop (floor passing), and lets everyone see where everyone else's mouse pointers are.
This is really just a prototype of a stop-gap measure, but it's fun to play with, and sort of useful on fast networks. To fully implement my grand vision of multi-user desktops, every application will need to be rewritten into something like Hydra. But in the meantime, I think that a tool similar to my VNC patch could allow for pretty decent application and desktop sharing. I envision something like this being used by a group of people so that everyone can see all the open applications, and can see what is being done in each one in real-time, and the limitation that only one user at a time can control each application is minimized with smooth control-passing.