ergophobe - 11:37 pm on Feb 3, 2012 (gmt 0)

It's hard for me to see how you can get away from, as a minimum, a networked drive.

Otherwise it seems like your other alternative would be to teach them all how to use git and they would do all their work under version control and branch, merge, resolve conflicts and commit to the shared repository. I'm sure that's going to happen.