Matt Sayles / Invision/AP 1 / 12
Matt Sayles / Invision/AP 1 / 12

By Corey Podell

Two of the music industriey's heaviest hitters -- Jay-Z and Eminem -- took the stage at the Wiltern Theater to perform a special, private concert for a star-studded crowd on Monday night. The rappers were celebrating their collaboration on the new DJ Hero game, the latest interactive music game from the hugely successful Guitar Hero platform.

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Famous fans who rapped-out along with Jay-Z and Eminem included Leonardo DiCaprio, Tobey Maguire, Ryan Phillippe, Abbie Cornish, Matthew McConaughey, Kim Kardashian, Christina Aguilera, Travis Barker, Pete Wentz, Ashlee Simpson-Wentz, DJ AM, Adrien Grenier, Amy Smart, Ali Larter, Jeremy Piven, Kevin Connolly, Michelle Trachtenberg, Alanis Morissette, Kelly Osbourne, Tony Hawk and many more. Was Beyonce home washing her hair or something?

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DJ AM (who was involved in the making and mixing of DJ Hero) and Travis Barker warmed up the crowd with a mash up of classic hits like "Teenage Wasteland", "Bohemian Rhapsody" and "Enter Sandman." DiCaprio, sporting a Mets cap and drinking a beer, rocked out to "Smells Like Teen Spirit" -- including a full-on head-banging session -- from the balcony with his best buddies Tobey Maguire and Lucas Haas. The guys apparently left their ladies (Bar Rafaeli and Jen Meyer) at home in favor of singing and rapping along to the lyrics amongst their little posse all night.

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Meanwhile, upstairs in the VIP section, Matthew McConaughey (with Camila Alves) roamed around in a wool cap sipping water, and Abbie Cornish and Ryan Phillipe hung out with their pal Breckin Meyer.

When Jay-Z went finally took the stage, Ryan Phillipe nearly exploded. He stood up and seemed to have a transcendental experience, rapping along with every word, every obscure lyric. Mid-set, his Abbie joined in, creating a spectacle of themselves. Just a few feet away, McConaughey closed his eyes and felt the music, man.

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At the end of Jay-Z's set, Eminem joined him on stage. The duo performed "Renegade" and brought down the house. Then, a mere 24 hours after his scandalous MTV Movie Awards appearance, Eminem performed his own solo set. He didn't mention the Bruno incident, but it was on the mind of many red carpet reporters. DJ AM called it, "Just silliness." We agree.

Plane crash survivor and, perhaps, the ultimate DJ Hero, DJ AM was popular amongst all the guests in the "Favorite DJ" category. Some honorable mentions included Samantha Ronson (said DJ AM), Boy George (according to Tony Hawk), Danny Masterson (claimed Simon Rex), and Kelly Osbourne gave a shout-out to her boyfriend, Luke Worrell, while also noting that, "If you call making a playlist and playing it DJing, then yes (I am a celebrity DJ)." Nice try, Kelly. Better start practicing some real mixing moves on your new DJ Hero kit, STAT.