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Sometimes, the pressures of working on a Big Important Picture get to be just a little too much; it then falls to the star to help loosen the mood of a challenging production, using anything and everything at their disposal to raise the spirits of cast and crew. And while George Clooney is considered a master of the genre, concocting elaborate ruses that can take months to unfold, his frequent Oceans co-star Brad Pitt tends to go for the easier laugh:

In an interview in Entertainment Weekly's Oct. 30 issue, the 42-year-old actor says he amused himself and his colleagues by yanking up his pants to give himself a wedgie, sticking out his rear and waddling about like a duck. "Throughout the movie, I'd walk around like this," he says.

"You've gotta find things to make you laugh during the shoot," he adds. "Cate (Blanchett) called it the Hungry Bum."

He explains: "When your bum's so hungry it's trying to eat your pants."

Less amused than Blanchett at Pitt's high-waisted antics was Angelina Jolie, who, upon being introduced to Pitt's "Hungry Bum" for the first time, sat stone-faced for several moments before delivering an earnest and impassioned lecture on how the two of them should be spending less time clowning around, and more time starting a foundation to help ensure no other bums go hungry ever again.