How about inside the PSU?
Never checked, but two things come to mind. First, if you attempt to open the PS while it's plugged in, you are in Darwin territory. There will be at least a few spots with 110v ac. Second, computer power supplies uses switching technology. Simply put, they use high frequency transformers for small size and low weight. I suspect that some combination of loose screwdrivers could encounter something higher than 12v. At the very least you might melt a screwdriver, and that's no fun.
My daughters PS filled with dust and caught on fire. Some combination of events fried the motherboard, CD and hard drive.