I have 4 x USB2 hard drives on my media centre computer. 1 is a 160gb drive that came with the computer and the other 3 are drives that I had laying around and bought cases for. The 3 I bought cases for are Western Digital 200gb drives. I bought 3 x Canyon external slimline drive cases which do a great job. They are quiet for a start which is a big plus and they also keep the drives well enough cooled to stop any heat related problems.
This is the case I bought and can highly recommend if you either have spare drives laying around or find that it's cheaper to buy the drive and case compared to a ready built drive:
http://www.canyon-tech.com/products/...e_HDD/CN-HDD35
I use the drives for storing home movies on from my VHSC camcorder and my DV camcorder. Some files are around 12gb and transfer speeds are good enough for my liking. It's also very handy if you want to move between computers as it quickly installs.
Regards...
Tom