“Pearl Harbor” producer Jennifer Klein‘s pre-Christmas party at her Brentwood, Calif., home turned into quite the girls’ night out. Christina Aguilera, Kristen Bell, Bridget Moynahan, Maria Menounos and Jamie Bergman (the Playmate wife of Rachel Uchitel‘s ex, David Boreanaz) all hit the dance floor at the annual shindig over the weekend. “They were all drinking Grey Goose martinis and hanging out,” says a spy. “Moynahan looked hot and was surrounded by good-looking men all night.” Jamie Foxx, Matthew Perry and Klein’s collaborator, Michael Bay, were among those who watched the action from the side.