generally speaking, it's a LOT cheaper to buy an internal HD and stick it in an external enclosure. this especially is true if you snag a deal on an internal HD (which pop up quite frequently at "deals sites"), and then you just pay another $30 or so for the enclosure. again, it's a lot cheaper than buying an external HD in the first place. and if you can plug a hair dryer into an electrical outlet, you can plug an internal HD into an external enclosure.