Found this joke on the web a while ago. I don't know who came up with it; it is posted on a bunch of sites. Here it is again:
Sometimes women are overly suspicious of their husbands. When Adam stayed out very late for a few nights, Eve became upset. "You're running around with other women," she charged. "You're being unreasonable," Adam responded. "You're the only woman on earth." The quarrel continued until Adam fell asleep, only to be awakened by someone poking him in the chest. It was Eve. "What do you think you're doing?" Adam demanded. "Counting your ribs," said Eve.
If you don't get the joke, read this:
Genesis 2:21-23 And Jehovah God caused a deep sleep to fall upon Adam, and he slept: and he took one of his ribs, and closed up the flesh instead thereof; And the rib, which Jehovah God had taken from man, made he a woman, and brought her unto the man. And Adam said, This is now bone of my bones, and flesh of my flesh: she shall be called Woman, because she was taken out of Man.