What's your best memory of a favorite hotel? Great service? A room with a terrific view? A romantic meal?

Or perhaps it's that ashtray you pocketed, the bath towel or bathrobe you took with you, the extra bars of soap or that pair of slippers that somehow found its way into your suitcase.

Admit it. Chances are that if you've stayed at a hotel, you've taken more than just the bill when you left.

There's a very good reason most hotel-room television sets are bolted to the wall; there's an equally good reason hotel-room bedboards, paintings, lamps and even soap dishes are fastened tight. "People will steal just about anything not secured," says one hotel manager. "And I mean anything."

The fact that many guests steal articles from their hotel rooms is not exactly a news bulletin -- but just what they are stealing these days might be a surprise. Would you believe . . . hotel telephones, entire room carpets, bathroom fixtures and even marble fireplaces?

"Losing things like ashtrays comes with the territory," says Patrick Board, general manager of the Mayfair Hotel in London. "We look at our ashtrays almost as hotel giveaways now" (the Mayfair replaces 8,000 ashtrays annually). "Still," he says, "so much of a hotel is on the honor system it's actually quite amazing that more things aren't taken."

But, in fact, more things are being taken. When the Intercontinental London opened in June 1975, management fully expected certain items to vanish. Indeed, dozens of ashtrays, towels and bathrobes checked out of the hotel.

"But we were clearly surprised," says spokeswoman Mary Gunther, "when we discovered that a guest had checked out not only with his luggage, but had also taken his bathroom door."

Then there was the case of the missing Egyptian bidet faucets. At the Ramses Hilton in Cairo, general manager Ahmed el Nahas investigated. The guest/thief turned out to work for a Japanese bathroom accessory manufacturer.

Far more puzzling are missing door signs from the Sheraton St. Louis. "These are bolted to the doors," says spokeswoman Deirdre Sullivan, "but the guests keep taking them as souvenirs. We can only assume that our guests travel with tool boxes."

In Malta, the headboards in most of the rooms at the Hilton contain eight-point Maltese crosses. General manager Anthony de Piro keeps extras on hand -- many guests have managed to pry off the crosses.

In Dubai, a guest who had been staying at a hotel until he could move into a more permanent residence invited the manager to dinner at his new apartment. "The minute I walked in I saw it," says the manager. "The hotel had furnished his entire apartment -- china, glasses, silverware, paintings and even seat cushions. I was too dumbstruck to say anything at dinner."

Sometimes, when a hotel adds a new item to a guest room, it fully expects it to disappear. When the Intercontinental in New York added giant bathsheets to guest bathrooms, the hotel prepared for a mass exodus of the large towels. "It never happened," says a spokesman. "The towels were so large people just couldn't get them in their suitcases. However, we did lose an awful lot of expensive washcloths."

Bathrobes still lead the disappearance list. "I'm convinced," says Robert Zimmer, president of Rosewood Hotels (owners and operators of the Bel Air in Los Angeles, the Remington in Houston and the Mansion on Turtle Creek and the new Crescent Court in Dallas) "that there are professional bathrobe collectors who must keep secret closets to display their booty. The minute we put our logo on the robes, they walked," he says.

When it was noticed at London's Savoy that the bathrobes, monogrammed with the Savoy logo, were disappearing, the hotel began to offer the robes for sale at 35 pounds each, but it didn't stop the robes from walking.

"Now," says Savoy spokeswoman Judith Dagworthy, "we offer to monogram the robes with the guest's initials for an additional five pounds. As a result, very few robes are stolen, and guests leave with a personalized memento of their stay with us."

The robe sales are only the beginning. Through its gift shop, the Savoy now also sells its chinaware, silver peppermills, tea strainers and condiment sets, as well as butter dishes -- all items that used to disappear in great numbers. Still, the distinctive pink Wedgwood ashtrays at the Savoy disappear with such regularity that the hotel keeps a standing order with the china maker.

"It's not that some travelers are kleptomaniacs," says Board, of the Mayfair. "It's just that when they're paying high prices for their hotel accommodations they somehow feel it's their right to do it."

Nevertheless, some guests will take just about anything. At the Beverly Wilshire Hotel in Beverly Hills, Calif., some guests have stopped just short of taking the bathroom sink.

"We've had expensive paintings stolen from guest rooms," says Beverly Wilshire spokeswoman Helen Chaplin. "What's worse," she says, "is what happened to all of our oriental scatter rugs we put on guest room floors. They disappeared. So we replaced them and had them sewn to the floor. They disappeared again.

"It's very difficult to stop the thefts," Chaplin says. "By the time housekeeping or security discovers something is missing, the guest has already gone."

Sometimes, the hotel unwittingly becomes an accomplice in a theft. When a Beverly Wilshire bellman arrived at a suite to help a guest check out, the man was waiting with his suitcases -- and the room's marble fireplace that he had just cut and chiseled out of the wall.

"Just taking it to get it repaired," said the guest nonchalantly. The bellman helped him take the fireplace out of the hotel. The guest and the fireplace were never seen again.

Every once in a while a hotel gets lucky. A guest staying at the Cavalieri Hilton in Rome ordered all his meals through room service and obviously selected the courses with a predetermined amount of cutlery in mind. When he had put together a complete service for eight, he checked out.

But the hotel had been keeping track of the missing silverware, and all of it was discreetly removed from his luggage before he left the hotel.

When the staff at the Beverly Wilshire noticed a sterling silver coffeepot missing from the room of a guest who had just left to check out, they notified the manager, who raced downstairs to intercept him. "We're so pleased you like the pot," he told the startled guest. "And because you're a regular with us, instead of just charging you our cost of $150 for it, we'll only charge you $75."

The man reached deep into his luggage, retrieved the pot and slammed it down on the checkout counter. "Not worth it," he said, and stalked out.

And occasionally stolen hotel goodies return after the fact. Not long ago, Andre Charriere, the manager of the Hilton International in Abidjan, Ivory Coast, received a large, unexpected package from the United States. When security officers opened the box, they found a tremendous amount of the hotel's silverware.

An accompanying letter explained that the guest had accumulated the utensils during many stays, had felt guilty and thus was forking over the large quantity of spoons, knives and, yes, forks. He begged the Hilton to "grant forgiveness and thus cleanse my soul." Charriere wrote the guest back, hoping that his act would "instill the same spirit in all who deprive the hotel of our operating equipment."