Jonathan Ive talks about the G5 design
Wired interviewed Jonathan Ive, the leader of Apple's industrial design team, about the G5.
Again, Apple gave great attention to every detail, here. For example, the fans used to cool the processors must be removed to add RAM. So Apple got rid of their power cord, and they slide into a pair of power slots.
Another example: the transparent plastic cover that sits inside the side door (visible in the QuickTime VR) is shaped (and used) to improve the air flow inside the machine. A purely functional component like this would have been paid little heed by the rest of the computer industry, Ive said. But it was made transparent so people could run their machines with the door off.
Typically Apple! :-)