A phrase coined by Terrell Owens of the Dallas Cowboys which signifies that one is about to put on a show, i.e. a spectacular performance. Refers to the act of getting one's popcorn before watching a movie.
Note posted on Terrell Owens' locker, October 2007:

"Dear Reporters,

Due to the magnitude of this week’s game and high volume of questions for the Original 81 (T.O.) about the other 81 (Randy Moss), I will be taking all questions immediately following Sunday’s game.

Terrell Owens

P.S. Getcha Popcorn Ready"

Piano teacher: "Timmy, have you been practicing that Beethoven piece for the upcoming recital? This is your chance to show everyone how much your skills have improved over the past few months."
Timmy: "Hell yeah, I've been on that shit like white on rice. I'm fin' to blow all you bitches away. I'm gonna rock that shit better than Ludwig himself. Better getcha popcorn ready! King Kong ain't got shit on me!"
by Nicholas D January 14, 2009
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