This thing sounds interesting. It's from the eDonkey crew.
"Kdrive is a virtual global hard drive. Anyone can create a folder (or group) on the Kdrive. Once you create a folder you are the folder's admin. As the admin you can create accounts for other users to access your folder. Every folder has a unique name.
Folders also act as chat rooms. You can talk to everyone who is also logged into the folder. You can also send private instant messages to anyone else."
Between exchanging public keys, passwords, and public secure folders this should get multi's juices flowing.
http://www.kdrive.com./security.html