I have two classes this semester both of which involve group projects. Since the members of my groups are spread out across the MassBay area and we all have very different schedules, it's been hard to come together in one central place to do group work and have meetings and such. No one else in the group has done any open source or decentralized development, so that's adding to the complexities. On top of that, we've got a couple of different operating systems involved.
We started doing meetings and document-editing together using Gobby. It has some minor syntax highlighting that helps, but more importantly, it allows us to talk using an irc-like pane on the bottom while editing a series of documents together in real time.
One of the problems I'm having with it is that I want to add Scheme syntax highlighting (not that there's much in the way of "syntax" in Scheme). I can't figure out where it would go, though. It's either handled by one of the libraries that Gobby uses or it's somewhere in the code and I just haven't found it yet.
The other problem I'm having is that it only allows you to edit text-based documents. I do realize that anything else would be wildly difficult. Still, it'd be nice to be able to "share" other artifacts other than text-based documents even if we couldn't all edit them. Right now we're iterating over other files by checking them into CVS and doing CVS update and also just sending things around by email.
Anyhow, it's definitely been really useful.