I agree... running a second hard drive is crucial and if you can afford it run an external raid system like SOME PEOPLE I KNOW (you know who you are p1mp) becaues then you've got your bases covereved. if a hard drive fails on your raid, who cares... you've got the data mirroed, replace it and get on with your day. if your bootable, or even second hard drive fails, well YER FUCKED. important data should never be on the same drive as the one you're booting from. good looking out View 1...
if you can't afford either like myself... once you've got the final mix done, burn the data to CD or DVD and seal it up some place safe.