Simon Cowell partied with lingerie-clad models at the infamous Playboy mansion on Saturday night. The TV mogul attended magazine founder Hugh Hefner's annual Midsummer Night's Dream party, held at the 83-year-old's Los Angeles home.

Jon Voight, Shaquille O'Neal, Jack Osbourne, James Van Der Beek, Ryan Seacrest, Randy Jackson, Shannon Elizabeth, Jon Lovitz and Hefner's former girlfriend Bridget Marquardt also attended the bash.

Kim Kardashian is to appear on "How I Met Your Mother." The socialite will be joined by "The Hills" stars Spencer Pratt and Heidi Montag in an episode of the sitcom in which they will play "magazine cover versions of themselves," a show source has confirmed.

Kim - who shot to fame alongside her family in reality TV program "Keeping Up With the Kardashians" - says she can't wait to appear on the show because she is a massive fan.