Prediction for Halloween evening: a tidal wave of ghoulish good times. But only if you attend the Tsunami (651 Okeechobee Blvd., CityPlace, West Palm Beach, 561-835-9696) party. The first wave starts at 5 p.m. (children welcome till 6:30 p.m.), and the tide goes out at 2 a.m. In between, revelers have a multitude of options -- down some spine-chilling cocktails, dance to DJ Mephisto's black magic beat, have your fortune told, indulge in a three-course prix-fixe meal for $75. There's no cover charge for entrance, but there are some rules, including a two-drink minimum and required costumes (after 9 p.m.). Of course, there are also rewards, such as the prize for best dress-up, a trip for two to the Shore Club in Miami Beach. And if you play your tarot cards right, you can extend your holiday cheer until the next morning, at which point you'll be able to nurse the ghost of your hangover.