A few people have asked how I make use of modern SCA SCSI disks with older machines.
Since high end 10000 or 15000 RPM 3.5" drives are overkill speedwise, and since most of us don't really need 300 gigs on our older machines, I've settled on 70 gig 2.5" disks such as the IBM 90P1316, the IBM 90P1313 and the IBM 26K5158. They're 10000 RPM drives which can communicate at Ultra-320 speeds ,so they're still much more than we generally need, but they're comparatively new, require less power than a 3.5" disk (although they still do require 12 volts) and they're cheap at around $15 USD ea