a "prince charles" piercing attached to a fishing line that's going to be casted. Hard. Or having that same piercing holding up a full bucket or water.
Also, I'm sure in Jackass they'd get permanent injuries and scarring like Tattoos, but how about getting a finger cut off? Then a guy in the room nearly EATS it? I'd be shitting myself. By about that time in the movie my stomach felt pretty queasy.
But as if it couldn't get worse, this guy gets a liposuction FULLY AWAKE WITH NO PAIN KILLERS. Stupid much? Needless to say, the jar was about 50% fat. The other half was blood. Later on they had some roulette type game and the loser had to drink a shot of the fat. This is where my stomach was at it's peak ;)