Power to the businesspeople who cram into this authoritatively noisy spot for lunch, eager to see who else is there and ciao down on innovative, new-wave Italian fare. The bright, bustling Campo de Fiori is so noisy that no one can eavesdrop on your conversation, and the menu alone will give you plenty to talk about -- from bold gnocchi al funghi for middle- management types who're strong enough to be seen eating dumplings to a buffalo mozzarella salad that says, "I haven't lost everything to the stock market yet." Liquid- lunchers who have lost a bundle sit at the bar downing limoncellos like Jolly Ranchers. Control your intake, though, because you can't risk a restroom stop: You might miss something.