I do something similar, if lower tech eric. I have two external backup drives. Each time I make a backup (and this includes all of my digital negatives), I take the new backup to work, where I store it the hard drive, and take the old one back home. So, I always have two geographically separated backups of my digital negatives (which honestly are my most treasured data). Short of the whole city being destroyed, I will always be able to recover most of my photos.

BTW, if you are not backing up somehow (CDs, DVDs, backup disks like my schema above, etc.) you don't really own your "negatives", you are just sort of borrowing them until the next crash. All computer hardware fails eventually, even Mac hardware. You should keep this in mind as you go!