one day last year I was in the gym and went to the lat pulldown machine in the middle of my workout. someone had it on 200 lbs or something, so I pulled the pin out of the weight stack, and the entire attachment fell on the back of my head. this was a really heavy metal attachment, must have been like 20-30 lbs fell on my head. I got really dizzy for ~30 seconds and had a big bump on my head, but that was somehow all that happened.
to this day, I'm kind of scared and cautious whenever I change the weight on those machines.
as i was typing a comment just now i remembered i left the electric stovetop on high. i have one of these moments every day at least.