Just bear in mind that if you want one that is portable and powered from the USB (or FireWire or PS2) port rather than a separate power supply then you will need a 2.5" (laptop sized hard drive) enclosure and with these you need to be careful about selecting one that has good heat dissipation characteristics (usually aluminium ones possibly with heat dissipation fins, vents and/or fans) and they may be limited to something like 120GB (the ones I was looking at recently were anyway). On the other hand if portability is not important then a 3.5" enclosure with a separate power supply will do and will be cheaper per MB. Other than that I can't really recommend specific models but would suggest that you browse/search for reviews and recommendations (there are lots of good hardware sites out there).