A blonde walks up to a Coke machine in a Las Vegas casino, puts in a few coins, and out pops a Coke. She puts some more coins into the machine, and another can of soda pops out. She keeps putting in coins, and cans of soda keep coming out.

A guy walks up behind her and says, "Can I please use the machine?"

"Buzz off!" she says. "Can't you see I'm winning?"