Tokyo is known for being densely populated and crowded. Living space is at a premium; hotel rooms are small or expensive or both.

Enter the capsule hotel, where a tube-like pod barely bigger than a coffin offers a bed for the night at low cost.

The capsule concept has been around for at least 30 years, starting out as lodging for businessmen working or partying late who missed the last train home and needed a cheap place to crash.

And judging from the dark suits and ties of the patrons entering and exiting the Capsule & Sauna Century Shibuya in Tokyo, the cramped beds remain largely a businessman's special. But budget travelers and other folks curious about a unique lodging experience use them too. So I decided to try it on a trip to Japan this fall, along with a visit to the hotel sauna.

At 5 foot 10 and 175 pounds (about 1.8 meters tall and 70 kilograms), I am almost exactly average size for an American. But in Japan, I felt oafishly big. In a sushi restaurant, I nearly knocked over all the patrons trying to squeeze past to my seat. On the metro, my heft encroached on to a second seat, often meaning the only open seat on the train was the one next to me. The pajamas thoughtfully provided by some of the other hotels where I stayed left me feeling like a sausage.

The Century capsule hotel exacerbated this feeling. I felt cramped from the moment I checked in, when I traded street shoes for hotel slippers too small for my feet. The sole elevator serving 10 stories was slightly larger than an airplane bathroom. Speaking of bathrooms, each floor of the hotel has a shared bathroom with several stalls and urinals (no women were on the premises). In a seated position, my knees nearly touched the door to the stall.

Then there was the actual "room." I splurged on "Deluxe" accommodation for 4,000 yen (roughly $50). My tube was long enough for me to lie down with an inch or two to spare. I could sit up, barely. And there was enough space for my small daypack next to me.

The capsules line a darkened room, stacked in twos like bunk beds on the 10th floor of the hotel. With a potential 32 guests in one room — more on lower floors — it's quite crowded.

There is no room for luggage. Checking in, you get a key to a locker (think small ones at the gym) on the second floor. It's big enough to hang a suit and leave the contents of your pockets while you hit the shared sauna and bath.

I'm sure a therapist would brand me repressed based on my sporadic dreams of showing up to work or an important function in my pajamas or birthday suit. But what about the opposite? In my trip to the sauna, I showed up clothed to a place where everyone else was naked.

When I rode the elevator to the shower and bath area on the third floor, I wore the snug hotel-supplied boxers and robe. The elevator let out into an empty room with cubbies, stacked towels and sinks and mirrors. To get to the bath and sauna, you need to slide open a giant steamed-up glass door. On the other side is no-clothes land. I blithely entered clothed, to the consternation of the men inside.

So I went back, ditched the clothes in a cubby and re-entered. But what next? Two large baths and a series of hand shower hoses with small stools reminiscent of hair-cutting stations at a salon were in the outer sauna area and a door led to the dry sauna.

After a ridiculous, pantomimed, naked conversation with a local, I showered, seated at one of the wash stations. Then I went into the sauna. I've never been in a sauna with a TV before. Nice touch, though the programming seemed to be a Japanese combination of game show and infomercial for a weight loss program, probably aimed at me.

When my body core temperature neared critical, I went out to the bath. First the cold, which nearly sent me into shock. Then the hot, much better, but quite crowded. Another wash off at the showering station and I figured it was time to turn in.

Climbing into the capsule takes a bit of maneuvering. I kept imagining climbing into a torpedo tube on a submarine, but fortunately no one fired me out.

The TV mounted in the ceiling offered more game shows and an adult channel, along with headphones to better listen. A dimmable light and built-in alarm clock rounded out the amenities.

I closed the blind at my feet and conked out. With a few dozen other people coming into the room through the night and clambering into their own capsules, it made for a less-than-stellar night's rest.

Really, a capsule hotel seems just like a youth hostel, but with a tad bit more privacy. Rather than open bunk beds in a common room, you get a little enclosed pod in a common room. The sauna and shared baths were clean and refreshing, but the heavy smoking in many common areas was less so.

All in all, I'd say a capsule hotel is worth a visit just to say you've done it. But don't expect a restful night. And depending on your size, you might emerge feeling like a giant.