I rencently purchased a 320Gb external harddrive, however it uses USB 2.0 which my powerbook don't have and is extremely slow using USB 1.0
An easy option I though was to get a Belkin USB 2.0 Notebook card, which, according to the instructions works on Mac OSX 10.2 and above without the need to install any drives as OS X should pic it straight up.
Soon as a put the card in the Mac it froze, nothing would work including mouse, keys etc. Tryed to restart but the Mac would not boot with the card inserted. Take the card out and all is well.
If anyone has any ideas drop me a line.