"Jingle bells, Batman smells,
Robin laid an egg
Batmobile lost a wheel, and .. " _____________ ?
What's your local variant on this?
EDIT: The consensus seems to be that either the Joker ran, or got, away, or broke his leg, or took ballet.
I should add at this point that another variant on the song ends with "Commisioner had to pay." But this seems to have been confined to the Pacific Northwest.