P2P Backups?

Robert X. Cringely suggests a new kind of peer-to-peer backup service whereby chunks of backup data are shared via a secured P2P network. Each user of the network acts a backup of the others, and the data is transferred, stored, and recovered in a BitTorrent-like fashion. Sounds like a great idea, although the security and privacy issues would have to be carefully considered. Nonetheless, it would be neat to see something like this implemented in a simple enough fashion for inexperienced users to be able to backup to an offsite location automatically.