I believe Ray Ozzie should be named the father of collaboration. Way back he created Lotus Notes, probably the first successful server based collaboration platform. Then he created Groove, a peer-to-peer collaboration system that doesn’t require any servers. He’s currently Chief Software Architect at Microsoft.

What’s so special about Groove? Jon Udell put it this way back in 2000:

Groove, enables groups of collaborators to form in a decentralized, ad-hoc, administrator-less fashion, within or across corporate or other firewall/NAT-governed realms. Groove is a peer-empowering form of groupware. These spaces collect all the documents, messages, and applications ("tools") related to a group activity. Everything replicates to each member's computer.

But at $225 a user, jumping in to Groove for an ad-hoc project probably will keep the members collaborating via email.

There is an alternative that is free - Collanos Workplace (http://www.collanos.com). 

Using Collanos is really quite easy. You install it on your computer. You create a workspace for a project. You invite other people to participate (they get a link to download the software onto their computer). 

You put files into the shared workspace, when the other people are on-line they get copies. If anyone makes a change, everyone else gets that updated version. The shared files can be just about anything. Plus you can keep a series of discussions, all nicely archived on everyone’s computer.

Think of how you might be collaborating with people outside your company - other sales people, peer networking groups, etc. The price is right, download it and start experimenting.