Welding while wearing flip-flops was always my favorite "stupid human trick". We had a guy in the car club I used to run who habitually had slag burns on his feet from doing this.When I was growing up, there was a large family that lived down the road from us that had a lot of boys. I couldn't believe how many times I would drive past there and one of them would be out mowing the lawn with the push mower in bare feet.