I Have 6 hard drives all identical down to the serial numbers i have 3 in my PC and 3 as Mirror backups.
All my installs are on C, all my Tracks are on D and all other s*** is on E.
I am also in the process of installing/Testing Win7. I have taken my C drive out and replaced with my backup for DAW install so if anything goes wrong i have peace of mind of putting my C drive back in the PC and of course what ever happens tracks on D are never affected.
Expensive but well worth it IMO.