6: Two atoms sitting in a bar. One turns to the other and says "I think I'm missing an electron".
"Are you sure?" says the other.
"Yes, I'm positive."
An ASCII character walks into a bar and orders three double-vodkas. Which he downs in quick succession.
"What's your trouble, son?" asks the bartender.
"Parity error", mutters the character.
"Ah, I thought you looked a bit off."