Our November sailing carried a jazz theme, and almost a dozen musicians performed from noon into the wee hours. Other Crystal cruises celebrate film and theater, food and wine, the big-band era and health and fitness. Five 2007 itineraries were offered in conjunction with the Smithsonian Institution.

Through partnerships with Berlitz, Yamaha and the PGA, respectively, the line offers free language classes, piano lessons and golf instruction on all cruises.

Land excursions are no less intriguing; passengers can fly a MiG jet over Moscow, test-drive a new Porsche in Leipzig, Germany, or hike nine miles through St. Emilion's vineyards in Bordeaux, France.

But, what about the grub?

FOOD AND FUN

The menu at the Silk Road, Nobuyuki ''Nobu'' Matsuhisa's first floating restaurant, tantalized the taste buds even before I could decide whether to choose lobster with truffle-yuzu sauce, black cod with miso or grilled Wagyu beef.

Silly me, imagining I would get to order.

''Remember me?'' the Silk Road's Filipino maitre d' uttered now-familiar words. ``I was your waiter years ago on the Symphony, and we prepared a special Thai dinner for you. We would like to do the same with Nobu's menu.''

And so the feast began. Soft-shell crab sushi rolls. Yellowtail sashimi with jalapeno. Rock-shrimp tempura. Lobster, cod and steak. One sumptuous course after another until we waved a white napkin of surrender three hours later.

The Serenity and Symphony offer Asian and Italian eateries as dinner options to the main restaurant. There is no surcharge, just a small recommended gratuity. Intimate multicourse feasts featuring rare wines can be arranged in a private room. Poolside luncheons include elaborate theme buffets and lighter fare highlighted by Wolfgang Puck's signature Chinois chicken salad.

And it's difficult to determine which is the more elaborate afternoon culinary diversion: Mozart tea, for which waiters dressed in period costumes serve European delicacies, or a festive ''chocoholics'' tea.

Entertainment is top-quality, too. Headliners have included Maureen McGovern and Neil Sedaka.

The ships' spas are designed according to feng shui principles and won top honors in Conde Nast Traveler magazine's 2006 reader poll.

Crystal's large ships allow for more enrichment and entertainment options and more open-deck space. Dining is never rushed. And fares, while hardly reminiscent of Carnival and Royal Caribbean pricing, are low enough that most passengers can afford to purchase booze and wine. Crystal Serenity’s Mediterranean voyages are priced from $2,995 per person, double occupancy, although some promotional fares are lower.