The zip cord one made me cringe.
The worst thing I think I ever saw was when I helped a friend put down new carpet on a concrete floor. The prior owner had wanted another wall outlet on the other side of the room and had used flat 300 Ohm antenna twin lead under the carpet presumably to prevent having a bulge. He had two young daughters sharing the bedroom. Thank God nobody ever put much of a load on it.
Really unbelievable about the twinax carrying 120 V.
I stayed at a mom & pop motel in Longview, WA in the summer of 1974. The owner shampooed the carpet one day. That evening I was standing barefoot on the still-wet carpet and went to turn on the wall air conditioner when WHAM - I was flat on my back several feet away. Dead short hand-arm-heart-feet.
Got my volt-ohmmeter out and sure enough — 220 VAC air conditioner case to the carpet. Complained to the manager and he brought in an electrician that morning who checked it out and pronounced “Nothing wrong here” with the motel manager standing there with us. I said “BS,” grabbed his VOM, shoved one lead into the still-wet carpet and the other on the AC case - 220 VAC. That was one sheepish electrician.
I tried to sue but got nowhere in that small town. Good thing it wasn’t a little kid or an elderly person who took that zap.