Cool thread..here are my top two from recent experiences:
Physiologically, I was totally caffeinitatedly drunk when it happened..
Situation: waiting for the elevator at the library at fifth floor, the highest floor in the building....
me directing towards ppl in the elevator:
are u guys going up?
everyone present in the elevator:

2nd)
3arabi Prof:
I need someone to volunteer..
3arabi Prof calls out a student's name and says,
"Come Habib and volunteer"everyone in class; "

"