Sexy Josh Hartnett shows all in New York City

Josh Hartnett revealed his naked butt to fellow dancers at a New York nightclub last week.'The Black Dahlia' star went 'commando' at the Beatrice Inn on Thursday night as he danced in low-slung jeans that slipped down to expose his manly buttocks. A witness told the New York Daily News newspaper: "One guest pointed out to Josh he was flashing a lot of skin, but he was perfectly relaxed and replied, 'It's cool, I never wear underwear.'"He didn't seem to care that he was showing his bare behind."Since splitting from Scarlett Johansson last November, Hartnett has been spotted canoodling with Brazilian supermodel Gisele Bundchen and enjoyed a romantic Caribbean holiday with actress Penelope Cruz.The 'Pearl Harbor' actor said he split from Johansson because their work kept them apart. He said: "It was difficult spending so much time apart with our different commitments and both of us flying all over the world."At the end of the day, we're just ordinary people and it didn't work."