Oh wow, that reminds me of another incident. In my early teens my dad was doing some home renovations, and had a bunch of power tools lying around. He had an electric drill with a three-pronged plug but only had an extension cable which accepted two prongs. So of course he just crammed the drill's plug into the extension cable as best it would fit. It worked, but left a good part of the prongs exposed. Upon seeing this I figured I could get the plug further in so I grabbed it and started pushing on both sides as hard as I could. Perhaps unsurprisingly this did not seat the plug any better but did cause my fingers to slip and contact the exposed prongs. This caused my entire arm to feel like it was numb and vibrating like crazy at the same time. It was such a weird sensation that I just had to grab the plug again to feel it a second time.. Reflecting upon this incident later I realized I probably could have been killed.

Did you know an American 10¢ coin is the perfect size to drop behind a plug-in night light, such that it gets stuck between the power plug prongs? You can then unplug the night light and the dime drops to the floor, with two impressive marks taken out of it.