A quick link before I go to bed: DIBS: Distributed Internet Backup System:
Since disk drives are cheap, backup should be cheap too. Of course it does not help to mirror your data by adding more disks to your own computer because a fire, flood, power surge, etc. could still wipe out your local data center. Instead, you should give your files to peers (and in return store their files) so that if a catastrophe strikes your area, you can recover data from surviving peers. The Distributed Internet Backup System (DIBS) is designed to implement this vision.
Thanks for the pointer, Erik. I’ll have to check it out in the morning.