External hard drives are all the rage these days - there are very good reasons to have an external drive that can easily be disconnected.
While nobody would have bought an Overdrive for backup purposes 20 years ago, the hardware would have still allowed you to easily carry all your data or even your whole workbench setup around and turn any A1200 (the one in the office, at your friend's place, at a copy party) into your A1200.
I call that a major feature.
