That was the case for our tablemates, Leo and Vivienne Wilmott of Atlanta, and Lori Gundlah and Jung Bin Song, a thirty-ish couple from Madison, Wis. ''We were going to go to Disney, and this just evolved,'' Gundlah said.

Many weekend cruises run Friday to Monday, which means you can board at noon Friday and make it to the Monday office meeting. By sailing on Thursday, Celebrity offers an extra day, and with it, stops in both Key West and Mexico. And you still get a day at sea when you can simply hang by the pool or get pampered in the spa.

FAMILIAR PORTS

As long-time South Floridians, we're old hands when it comes to these ports. Still, we found plenty to enjoy.

Key West has gotten too T-shirty for many tastes, but it clings to both history and quirkiness, and for those who resist the urge to test all 72 bars on Duval Street, the Audubon House, Hemingway House and the Key West Museum of Art & History offer worthy alternatives. (If you get there before the end of the year, don't miss the Seward Johnson exhibit of icons -- think Mona Lisa and American Gothic -- in sculptural 3D.)

Cozumel feels a lot like Key West with a Mexican accent, but the shopping options are different -- silver jewelry makes for smart, affordable presents -- and so are the ship's shore excursions. We had already visited the Tulum ruins, and the Mexican cuisine workshop recommended by friends seemed bound to derail our never-ending battle of the bulge. Instead, we opted instead for snorkeling Cozumel's famous reefs.

If we had never wanted to leave the ship, well, we would have had more than enough to do. Onboard entertainment was lively, sometimes even smart, but never ear-crashingly loud. Sure, the sail-away band played the steel-band standards, but they also threw in plenty of Baby Boomer nostalgics like Electric Slide and Tooty Fruity, and throughout the trip, choices included classical, rock and DJ dance tunes. Funny man Louis Johnson delivered a witty show that completely dodged too-common sophomoric raunchiness. Cosmetics seminars, wine tastings, casino tournaments, gym workouts, a self-guided audio art tour, and -- OK, you gotta have it, a shuffleboard session -- filled out options. The wireless Internet service (yes, we're talking workaholic) functioned reasonably well.

Our day at sea left us with too many options and not enough time or energy to try them all. I'd already hit the spa -- the Thursday sailing day treatments were a relative bargain -- and fantasies of hard-core gym time had devolved into a series of leisurely naps. We did take a couples massage class, which would have been useful had either of us practiced what we learned.

Oh well. Laziness and inertia are the drawbacks -- or is it the benefits? -- of a weekend cruise. ''We haven't done as much as we expected or read as much as we expected,'' said Patti Hart of Washington, D.C., who came as a break from house renovations. ``We've totally relaxed.''

SOME SNAGS

That's not to say that everything was perfect. With 1,800 passengers, Century carries far fewer passengers than many ships, but we still found ourselves in long lines (though they moved quickly.) Buffet offerings at breakfast and lunch were predictably standard, and occasionally not even worth the calories. Finding a chaise lounge on our day at sea proved to be a mission impossible.

And of course, there was that dinner we didn't have in Murano.

Except that we did.

With persistence, The Husband got us on the restaurant's waiting list. And when a cancellation came up, we scored a table.

Though we eat out frequently, this evening felt special, like an actual date. Service in the lushly intimate Venetian room was crisply formal yet friendly, the cuisine deftly prepared.

We bypassed the recommended seven-course tasting menu -- too much food, even for a splurge -- and ordered a la carte: foie gras seared oh-so-perfectly, diced vegetables with chilled lobster medallions, a yummy sea bass grilled with dried tomatoes and herbs, Dover sole (it was slightly overcooked, the only disappointment), a selection of cheese and a chocolate soufflé. Dishes were often finished at our table, creating the ambiance that you find in Paris and the grandest cities of the Far East, but rarely in the tropics.

Worth the price -- and even the now-erased hassle. On such a long languid weekend as this cruise, a single moment of adversity is soon washed away.