To most Americans, renting a hotel room by the hour means a drive to the edge of town, an embarrassed check-in, a stained and threadbare wall-to-wall, and grunts from the next room. That formula wouldn't work in Japan, though, where privacy, decorum, and hygiene are all held at a premium. Yet the demand for hourly rooms is much higher in Japan, thanks in part to a more chauvinistic society that doesn't frown as heavily on philandering husbands as well as to a living-space shortage that drives even married couples to seek occasional trysts outside their cramped, thin-walled apartments.

But in Japan every problem seems to have a technological solution. The result in this case is the multibillion-dollar "love hotel" industry.

It's hard to miss some love hotels. They can be astoundingly gaudy affairs on the outside, often done up to vaguely resemble such out-of-place icons as cruise ships, wedding cakes, or the Statue of Liberty. Otherwise, love hotels are paradigms of discretion. You drive into a parking lot whose entrance is covered with long cloth fringes to foil prying eyes. Various types of pull-down or clip-on devices are available for covering up your license plate, lest a jealous spouse take to cruising the lot in search of your car.

The most impressive concession to privacy offered by many love hotels, however, is the ability to check in and out without interacting with any staff. Just inside the entrance to the hotel is an electronic screen that tells you the numbers of the rooms that are vacant. You then make your way to one of the rooms and gain entrance by inserting yen notes (typically about $30 an hour) into a computerized lock. The door flies open, and that room number disappears from the screen at the entrance.

High-tech touches inside the neat, if small and slightly garish, rooms can include wide-screen-video karaoke and a remote-controlled sound system that offers not only dozens of music channels but also noises such as gongs and crowing roosters (hey, whatever turns you on) and even the sounds you would hear in a train station (to be played as background when you phone your boss or spouse from the room to say you're going to be late).

When you leave, maids are electronically summoned by the computerized door lock to thoroughly clean and sanitize the room. One hour and five minutes after you first walked in, the room number is back up on the board.

-- Michael P. Cronin