Maybe before the days of GFCI's or before the days I had one outside I was like 15-16 YO sanding a car in shorts, no shirt and bare feet on the grass. I didn't notice the rectangular shaped electric cord was frayed. I caught the cord between my toes, so I had this nice connection between by toe and the large area of the side of my torso.
No one was home either,
Surprisingly, I thought of consciously screaming. It worked! I was able to get free. Kinda like when something hurts and you make something else hurt, the stuff that huts more takes over. So, it's useful info and something you won't find in school. That incident. was a "must have" a GFCI.
The bathroom still doesn't have one. The hair dryer might be the only thing used there and it has an integrated GFCI. A rug shampooer/vac also has an integrated GFCI. I Have to try to fix another wet/dry vac by relocating the switch and I'm debating whether to get one of those cord varieties. The basement could use one, but there is a fridge and freezer down there.
I don't test 9V batteries with my tongue anymore.