About a month ago, my backup drive (Western Digital MyBook 500GB) failed. Unfortunately it failed as the hard drive on my laptop reached capacity and I was transferring files back and forth. Luckily I had 90% of my Livewire photos backed up on one of two laptops, and luckily I (We Fix Macs in Palo Alto) was able to recover 95% of my personal photos.
I've implemented a more rigorous backup process for all photos - it begins with the transfer of raw files from my camera's compact flash to my laptop and includes a DVD backup of the raw files, a copy on my laptop, and a copy on my primary external drive backup before I erase the images from the camera's compact flash. I have a similar process for edited files - another copy of the raw files with intelligent names applied, two DVD copies of edits and proofs, and copies on both my primary and secondary external drives.
In the process of going through the recovered data - organized solely by file type, in no particular order - I discovered abstract art. Check out the Not if... When... Hard Drive Recovery Failure gallery and see how some digital negatives were transformed. Vote for your favorite.