New York nightlife queen Amy Sacco, celebrating her disco-themed 40th birthday party Thursday night at the Hard Rock Hotel with 200 of her closest friends, including Benicio del Toro, Jonathan Tucker, Angie Harmon, Dean Cain and Brett Ratner. After dinner at AGO, the party moved to Body English, where she joined 100 additional friends. A Donna Summer impersonator led the club in "Happy Birthday," and Sacco was surprised with performances from mini-Michael Jackson and Milli Vanilli impersonators.