More notes:

(1) Not all of these enclosures claim ATAPI compatibility -- ensure that you get one that can do both ATA and ATAPI -- my el-cheapo one does both, and so does my expensive one.

(2) One can mount a removable IDE drive rack into one of these enclosures, allowing the drives to be swapped in and out without dismantling it or fiddling with screws. The rack will project out the front by an extra .25" or so -- looks slightly ugly, but works and is quite versatile. For example, I sometimes remove a drive from an empeg and stuff it in to the rack to do direct drive-to-drive cloning.

(3) All of this is for 3.5" enclosures. There also exist 2.5" ones, that can optionally power the (laptop) drive directly from USB2. Sometimes this burns out the host's USB2 port due to excessive current draw on spin-up. Most of the time it doesn't.

Cheers