If you thought car dealerships were good for only one thing -- selling automobiles -- then you haven't been to Ragtops (2119 S. Dixie Hwy., West Palm Beach; 561-655-2836). This vintage-car dealership, specializing in convertibles, is also a special-events facility. Catered affairs take place in the second-floor showroom, which requires taking a freight elevator up. The idea of having a party surrounded by antique autos and memorabilia is so charming I'd recommend it to anyone, but particularly to parents of high-school seniors. That way, you can throw your kid a graduation party and buy him or her a new old car at the same time.