Yogurt Poop
Have you seen this commercial for the yogurt that keeps you regular -- "Activa"? One young female woman doesn't want to go out (implication -- clubbing or whatever the kids are calling it these days) because she is "bloated". Roomie, of course, is regular -- because she eats Activa. EVERY DAY.
Then they show one of those medical looking pictures. It looks a little something like this:

Then this:

Oh, I see! Some yellow balls will move around, then form an arrow in (on?) my stomach pointing down. Right. That makes perfect sense.
Unless... wait, I think they mean it'll make you poop! That arrow means poop. Come on Dannon -- quit skirting the issue. Keep it real. It's poop you are talking about. POOP POOP POOP!
Also funny -- the bacteria "only found in Activa" is called Bifidous Regularis (TM). They trademarked the bacteria, and called it "Bifidous Regularis".