The Rusty Moose is executed when one is in the rear mount position. While slamming away, you poke your fingers into the asshole one at a time, to include the thumbs. Next you shove your thumbs into the ears of the subject, maintaining coitus, opening your hands in a moose-antler fashion and bellowing loudly.
"Yo, dude, I gave the Patti the Rusty Moose last night."
-Verb- The act of pulling a Rusty Moose can be summed up by making a fool of, and/or embarrassing, humiliating, degrading, spoofing, or fa-noodling ones self. And other wise, making yourself look or seem idiotic, dumb, retarded, stupid, ignorant or worthless. May also be implied when ill-referencing something, or refusal of dancing The DK dance.
Guy 1: I got arrested for asking a cop that pulled me over for drunk driving, to hold my beer while i tried to run away.
Guy 2: Dude, you Just pulled a Rusty Moose