I didn't know about `bup`! Thanks for the reference! I was reading the README and it indeed looks pretty great. Have you been using it? What's your experience with it?
The ability to recover from a left state seems pretty amazing:
> You can back up directly to a remote bup server, without needing tons of temporary disk space on the computer being backed up. And if your backup is interrupted halfway through, the next run will pick up where you left off.