Seconding Tarsnap. Can't recommend it enough.
Tarsnap enables you to separate out the ability to write/read/delete. So a compromised box could at worst be used to inflate your tarsnap bill but not to wipe out all your backups.
Thanks for the follow-up.
I'm launching the Rest Backup beta next week.
I know of organisations that diligently back up their data, but fail to regularly check that they can restore from backups.
The server that I've done and tested restores for is only about 1.5 gb of information/configs.