I saw this advertisement on a bus stop in Chicago and, naturally, had to go back to snap a photo.
At first, I didn't get it.
When I did, I busted out laughing and promptly reported the sighting to my friends.
Go ahead, click on it to zoom and take a better look.
If you're not from Chicago, here's a hint.
And here's another. Ahhh, still makes me laugh.