An intimidation tactic.
To stand, extend the arms with the elbows and wrists bent. Proceed to wiggle the hips and open and close your fingers in a claw-like fashion.
*person doing crab skuffle in the distance*
Joe: "Oh damn! Look at that crab skuffle, bro!"
Greg: "Woah!"
Guy 1: Did you hear about Kai? He got into a Strufflet.
Guy 2: Damn, where?
Guy 1: At the gay bar downtown.
Guy 1: I hear Strufflets are common over there...