So this one is an oldie, but it's a goodie.
Seems God was just about done with creating the universe -- but he had two extra things left over in his bag, so he decided to split them between Adam and Eve.
He told them that one of the things he had left was a thing that would allow the owner to pee while standing up. "It's a very handy thing," God told them, "and I was wondering if either one of you would like that."
Well, Adam jumped up and down and begged "Oh, give that to me! I'd love to be able to do that. It seems just the sort of thing a man should be able to do. Please. Please! Pleeease! Give it to me." On and on he went like an excited little boy.
So Eve just smiled and told God that if Adam really wanted it so badly, he should have it. So God gave Adam the thing that allowed him to pee while standing up and he was so excited. He whizzed on the bark of a tree and then went off to write his name in the sand, laughing with delight all the while.
God and Eve watched him for a moment and then God said to Eve, "Well I guess that leaves you with the other thing ... what was it again? Oh yes, multiple orgasms..."
I used to have a friend who was a girl and peed standing up.