High School Musical hottie Zac Efron is hanging with a new crowd this summer. He has signed on to appear as himself on an episode of HBO's Entourage. The sixth season premieres on July 12. Zac was spotted filming his scene in Beverly Hills yesterday at the Niketown store. Sports stars Tom Brady and LeBron James, as well as rapper Lil Wayne, are also expected to make cameos on the new season.