Is there any kind of peer2peer file server? Say we have a few laptops laying about and wish to share/mirror each other's files.
A creates file wishlist.txt
B, C and D all mirror this file on their own hard drives.
B edits wishlist.txt, A edits wishlist.txt and there's a conflict. File splits into wishlist.B.txt and wishlist.A.txt otherwise the file is merged peacefully.
Versioning/ability to revert files .etc Locking file ownership...
It'd be a good collaboration/sharing tool for working with artwork rather than requiring a central server. Git is too restrictive and pedantic for anything outside of code.
Have you seen: http://www.foo.be/forban/ http://wiki.daviddarts.com/PirateBox
 though for versioning, and more specifically merging, this wouldn't help you.