Yeh, you'd have to shoot it from the side-panel side, otherwise you'd risk the metal peeling back in such a way as would short out the motherboard. It would definitely be safer (and might look almost as good) to just take the side panel off and shoot that.
I believe the sky is the limit. There has been a entire arcade case modded to have a PC inside, a pumpkin, a fish tank, a old school boom-box. I think it just has to have a computer inside and it qualifies!
“Always do right. This will gratify some people and astonish the rest.” - Mark Twain