I've just spent the weekend moving the last few bits out of my parents' house - just a few odds and ends that never got prioritised (yes, I took my time). This includes a few old computers. I wrapped them up in a bit of bubble-wrap for transport. From this experience, and the fact I want to transport them, and the fact that people often want to stack up a set of computers, reveals a useful design priciple: A computer should be able to lie safely on any face.
You'd have thought this would be obvious. A decent number of machines have their ports on the back recessed in order to meet this point. This is very useful if the ports are mounted directly on the motherboard, where excess pressure on the back can break the whole thing. BNC connectors (as seen on 10Base2, and some video connectors) are particularly bad, as they're quite deep and stick out far.
Anyway, the HP 9000/340 loses badly, with a full 4 BNC connectors sticking way out of the back of the machine, completely unprotected. *sigh*