The quintessential celebrity-owned restaurant is New York City's Tribeca Grill, which celebrates its 10th anniversary next month. It's located on the ground floor of Robert De Niro's Tribeca Film Center (an old coffee factory), and its investors include De Niro (of course), Sean Penn, Christopher Walken, Mikhail Baryshnikov and rap czar Russell Simmons. Among the patrons are Miramax moguls Bob and Harvey Weinstein, who hold court there with everyone from Mick Jagger to Hillary Clinton. "Things work best when celebrity owners come as guests and let otherpeople run the show," says restaurateur Drew Nieporent, who opened the Grill with De Niro. But Bill Murray, another investor, doesn't agree. When he's in town, he checks coats and plays doorman.