What do stars do on their days off? Tom Cruise, for one, went to the circus. Taking a break from shooting their current “Vanilla Sky” in Manhattan, the star and his director, Cameron Crowe, attended “Barnum’s Kaleidoscape” in the city’s Bryant Park yesterday. The show is the latest holiday spectacular to hit the Big Apple. After the performers’ final bows, Cruise, who attended with his two children, Isabella, 7, and Connor, 5, chatted with star clown, David Larible, a Kaleidoscape spokesperson confirmed. (During the show, the star held his younger daughter on his lap. Because he wore a hat, most of the spectators apparently didn’t recognize him.) Crowe, who was accompanied by his wife, Nancy Wilson of the rock group Heart, was said to have taken a special interest in the lighting of the show. Wilson, who owns Arabian horses, meanwhile, chatted afterward with the show’s aerialist and horse trainer, Sylvia Zerbini. No word on any of the visitors’ thinking about running away with the circus.