The ultimate in testing your defences
Although illegal, it's not uncommon for US homeowners to booby-trap their property against home invasion. But, if going down this route, it's advisable to have a clear recollection of where those booby-traps are placed, and how they're triggered.
Ronald Cyr, 65, of Van Buren, Maine, discovered this the hard way on Thanksgiving. He was shot, when a door that he had designed to trigger a handgun did exactly that. Although he called emergency services to say he'd been shot, he died. Bloody idiot.
Still, at least he knew that it worked as intended. Which must've been some consolation in his final moments. (LOLZ)