Flopping onto a deck chair between buffets and bingo may seem like a typical day on a cruise, but now more and more ships that feature specialized itineraries are setting sail.

Whatever the interest — from NASCAR to nudity — there's a trip for every traveler.

"Theme cruises have been growing in popularity for about six years," Karen Bohning, spokesperson for Cruise Lines International Association, said. "We're seeing lines that never used to offer theme cruises adding a few each year."

Fans of the TV program Antiques Roadshow, for example, can take the skills learned from the tube to the British Isles on a Radisson Seven Seas cruise.

The 11-night voyage is "very much along the lines of the BBC show, with experts from the program aboard, including an Orientalist, a former Sotheby's director and a collectibles specialist," said Andrew Poulton, director of marketing at Radisson.

The experts give lectures and lead groups to find their own treasures at ports including Ireland, Scotland and Wales.

On another cruise, the guests may seem jittery, but it's not from seasickness. Carnival Cruise Line offers the Stop Smoking cruise on which experts help people quit smoking, adjust to recovery symptoms, manage stress and fight the urge to pick up cigarettes again.

If the classes don't get you to quit, the penalties for lighting up might. Violators who are caught taking a puff must disembark, forfeit their fare and return home at their own expense.

But perhaps the most popular niche trips are sport-themed cruises where professional players from football to NASCAR attend, said Bohning.

"Guests have a lot of close interaction [with the athletes] that they might not usually have the opportunity to have outside a cruise," she said. "You get to enjoy the experience with them."

NASCAR champion Rusty Wallace is partnering with Carnival for racing-themed voyages. During a cocktail reception, guests will be able to get so close to Wallace they might smell the grease. Raffles with prizes such as race passes and an opportunity to be on Wallace's pit crew are also planned.

And for people who get thrills from chills, Abercrombie & Kent goes on icy adventures to Antarctica and the Falkland Islands. The 17-day voyages attract travelers "interested in an educational experience, seeking high-quality hands-on exploration," according to Bob Simpson, vice president of sales and marketing for the line.

The Explorer, an expedition ship that holds 96 guests, can get right up to the ice — while other ships drift at a distance. Passengers take treks that follow the footsteps of early explorers, kayak pristine channels and see wildlife such as penguins and seals up close. A team of geologists, zoologists and historians give lectures onboard and expand on the lessons ashore.

Simpson said the cruise has become more popular because it is safe from a conflict standpoint in a post-Sept. 11 world.

"The type of people we tend to attract do adventure-type programs — a safari, a trip to Egypt — and right now those destinations are off the map for some people."

But not everyone likes to bundle up on vacation. Some prefer to take it all off — on nudist cruises. Bare Necessities, a nudist travel company, charters ships from lines like Windstar and Carnival for trips where a toothbrush is about all that's needed.

The cruises offer the usual activities with a twist: nude sunbathing, scuba diving and tennis, said Nancy Tiemann, president of Bare Necessities. Clothing, however, is required at dinner for health code reasons.

Tiemann, who charters about four ships each year, said the cruises' popularity has sailed.

"We're selling out 2,000 passenger cruise ships months in advance," she said. "More and more people are realizing ... the preconceived notions [people] had were unfounded — that something kinky was going on, that this was a swingers thing. This is a wholesome and fun vacation with people who aren't uptight. You can really leave your clothes and your stress behind."

But whatever your interest, Bohning said there's likely a cruise for you.

"If you have a certain interest in something, it's a great way to get together with people who share the interest, meet experts in the field and have a vacation."