There's also drives with a 4-pin DIN connector for 5 and 12v. And there's no standard for which side 5 and 12 are on.

Have killed a disk using the wrong power brick. And it had some data on it I had nowhere else.

Got the data back years later when I bought another similar drive and board swapped them - but this was in the era of 750GB drives where you could do that and it'd actually work.