I learned that you shouldn't take a drink at a pivotal moment in a TV comedy show, lest you prove your mother right and drown in a drink of water.
I was watching a Friends episode where Rachel and Monica watch Ross's son. I can't remember exactly what happened, but somehow the baby bumped his head. When they told Ross about it later, he started giving them grief in the form of he probably now has brain damage, etc, etc. He kept going on and on to freak them out, and then started laughing. While laughing, he started to run from them in their apartment, and turned around and ran right into the support pole that was in their apartment.
It was just as that happened that I took a drink of water. I found that day, that one inhales just as they start to laugh. I was trying to cough (hard to do when all you have in your lungs is water) and laugh, again, hard to do when all you have in your lungs is water. I was freaking my kids out, because I was probably turning blue.
Yes, you really can drown in a glass of water...