"I'm pulling this from my answer to another SU question:
The goodness of backup solutions (from best to worst):
multiple offsite + [multiple] onsite - Best possible solution Offsite + onsite - Great for nearly all uses (computer melts and takes your backup with it, you just get your data from off site) Single offsite - Alright, could be better (what if their data center--or your safe deposit box--gets taken out by a hurricane or meteor?) Onsite only - Worst working backup (only protects from hardware/software/user faults not disaster/theft) No backup - Don't come crying when you lose your data
I use and like Mozy for backing up into the cloud. I'm using it for all of my documents, configuration files, scripts, photos. Anything I can't just download again. I also really like Jungledisk, but it does get more expensive as your data gets up there in quantity. I don't backup my purchased media (unless it's from Apple) as I can just download it again.
Using either Mozy or Jungledisk you can encrypt all of your data such that even your data stored on their servers is compromised, it would need to be decrypted. Because of the length of key each service uses, decryption is compute intensive and you only really have to worry about the NSA (who--let's face it--are going to get your data if they want, no matter what)."
At home, I use a Drobo -- a 4+ drive enclosure that automatically puts it into a RAID setup (1 if you have two drives, 5 if you have three or more, and 6 for some higher models). Also allows you to swap drives for higher capacity ones should you need to expand. I highly recommend that.
