I keep getting this error lately when I try to copy large (200+ MB) files over to my external. Following this, the disk becomes unresponsive and I got to unplug it and plug it in again to work.
The copy process also is unreasonably slow.
It is worth noting that this happens on Windows too, so it's not the notorious "Error -36" bug OS X had prior to 10.6.3.
The disk is a Western Digital 3200BMV.
edit: Thanks for the replies so far