My desktop has 4 physical drives, but only 3 "Drive" letters..

Basicaly, i raid(0) my two 20 gigs, I cut of a 10 gig section and mirrored - raid(1)it to a physical 10 gig drive, then a have a 27 gig with my second OS.

Basicly, anything i want to keep, i dump to the 10 gig mirror. I don't need to worry about backing up, etc.. From time to time i'll burn stuff, but that is more for space considerations.