I remember some guitarist or singer or something like that on the Howard Stern Show about 15 years ago who claimed he pissed inside Madonna once. I can't remember what his name was though, which is an unforgivable shame since he's been my hero ever since.
One of my roomate's in college used to piss the bed regularly, due to being piss drunk. I was usually drunker than he was though and never once pissed the bed.
Also, I was home for the Summer working and he stayed down at school. When I returned, he told me he finally went to wash his sheets for the first time in probably a year and found a dead mouse in his bed.