USB 2 drive enclosure recommendations/warnings?

[Todd Pytel <tppytel@sophrosune.org>]

I'm looking to pick up a USB hard drive enclosure for backup purposes,
and was wondering if there were any success/failure stories I should be
aware of.  I need an enclosure (not an external drive) because I'll also
be backing up (via network) some OpenBSD machines, which don't support
USB 2 - so the drive would have to be removed from the enclosure and
attached directly in case of a restore.  The enclosure doesn't have to
be built for constant movement - I won't be carting it around places,
except for the trip back and forth to the closet every couple weeks. I'd
rather not spend a fortune, but I'll pay what I have to to get something
that does the job.

Anything I should be looking for?

Thanks,
Todd