Brad Pitt, Cameron Diaz Help Expose Jimmy Kimmel's 'Relationship' With Ben Affleck

Earlier this month, comedian Sarah Silverman revealed she was "f***ing Matt Damon," live on boyfriend Jimmy Kimmel's show and last night, the late night talk show host got his revenge, revealing he's been "f***ing Ben Affleck."

Silverman revealed her liaison with Damon through an expletive-laden music video, featuring the "Bourne Ultimatum" star, but Jimmy went one step further.

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Jimmy recruited a cast of Hollywood's elite, and of course, Ben Affleck, for his video response. Throughout the video, Ben and Jimmy get cozy with each other, take a drive through town and at one point share a walk in matching cut-off jean shorts, with each other's hand snuggling each other's backsides.

Brad Pitt made a cameo as a delivery guy, one who serves up a cake, emblazoned with the words, "Congratulations on F***ing Ben Affleck."

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Other stars singing in the "We Are the World" style clip included Cameron Diaz, Huey Lewis of Huey Lewis and the News, Don Cheadle, Rebecca Romjin, Christina Applegate, "Lost's" Dominic Monaghan, Pete Wentz of Fall Out Boy, Meatloaf, Josh Groban, Joan Jett, Robin Williams, Lance Bass, Christopher Mintz-Plasse (aka "McLovin'"), Joel and Benji Madden of Good Charlotte and Macy Gray.

"Indiana Jones 4" star Harrison Ford also made a cameo in the clip, lending his vocal stylings to the medley and blowing a kiss to Ben and Jimmy as they cruised through town.

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