I had this bill as a kid, and it held a scary fascination. Like money from other countries that sort of looked like our money, it had that alternate-universe vibe. But that thing! That stone manhole! That creature in the middle sticking out his tongue! It seemed to indicate something ancient and implacable and nasty at the heart of the nation.

More on the Aztec stone, and the charming rituals that accompanied it, here.