Japanese engineers thought that allowing Matt Lauer to ride the on the Today Show this morning was "too risky," but I sweet-talked them into letting me roll through Times Square on it. Cybernetic unicycle, meet New York.

In return for permission to use the U3-X in Times Square, we promised Honda that we would make it abundantly clear that what we tested was a prototype. We repeat: the Honda U3-X is You can't buy it now, nor will you be able to do so at any time in the near future.

What's it like goofing around on an oversized, self-righting suppository in front of hundreds of tourists? Surprisingly, not as embarrassing as you might think. You get the feeling that people from places without tall buildings expect to see a man perched atop two ergonomic butt pads while accompanied by a fleet of worried Japanese men in unassuming suits. You get the feeling that they would have been disappointed if I hadn't whirred past them on one wheel.

Compared to the I test-stumbled in Times Square last year, the U3-X attracts much more in the way of friendly curiosity and far less in the way of that-guy-is-dangerously-insane. Maybe it's the lack of a surgical-white crotch cup that makes the wheelie stool more palatable.

The Honda Walking Assist Devices attempt to augment human mobility with robotic power. Earlier…

But what am I doing piloting a Japanese personal-mobility device through the streets of Manhattan? What is Honda, a car and motorcycle maker, doing making a wheelie stool? The answer to both is slightly longer.

Honda has always approached the business of making vehicles with a certain sense of imagination. You get the feeling that, although most of the company's current products are mind-numbingly boring, Honda is always trying to find its way into the future. Right now, the future for Japan is old people. Lots of them.

By 2020, more than 25 percent of the Japanese population will be over 65. Those old fogeys are going to have to work until a later age and their kids won't take care of them even when they're retired. That means they need ways to extend their lives beyond broken hips and atrophied muscles. Devices like the U3-X and Honda's Walking Assist Devices are exploring new ways to extend the mobility of the elderly and people suffering from physical handicaps.

With the U3-X, Honda hopes to create a way for handicapped people to move through public places in a natural way, unencumbered by external supports. That's why the device is so slim — sitting between your legs, it allows you to interact with the world as you normally would. If you bump someone in a crowd, it's with your shoulders or arms, not a set of metal handlebars. Your hands are left free to interact with things around you.

At the heart of the U3-X is Honda's proprietary balance-control system, initially developed for the ASIMO bi-pedal humanoid robot. It senses lean angles and acts to hold itself upright or move in any direction through an omnidirectional wheel. That wheel is composed of one normal wheel that rotates forward and backward and multiple smaller wheels mounted sideways around its circumference. All those wheels are essentially working all the time, holding you upright and moving you in any direction you lean.

Let's get some specs out of the way: The U3-X weighs just 22 pounds, meaning it's easy to pick up and stow in the trunk of a car. Its lithium-ion battery has enough juice for an hour of riding, and a recharge takes about 90 minutes at 110 volts. Top speed is 3.7 mph. The U3-X is also self-righting, to a point — the only way it can keep its thin, tall body upright is through the single wheel. If you push it too far past the vertical, it will fall over.

There's only one button on the device. Push it, and a light will flash green when the U3-X is ready to support itself. Fold out the seat pads, fold down the foot pegs, sit down, and you're ready to go. The only way you interact with your transportation is by leaning, but not as far as you might think. (I made the mistake of leaning too deliberately, which results in jerking motion.) The trick is to think about leaning — the U3-X will then sense your subtle movement and respond accordingly. It's crucial to center yourself on the device, as any weight bias in any direction will throw off its ability to sense movements. It's not difficult for a new rider to pilot the U3-X since it takes care of balance, but it is a little tricky to master the relaxed subtlety necessary to change direction quickly or track in a straight line. Your natural tendency will be to tense up and react unnecessarily to every little thing.

Once you're used to the sensations, you can zip forwards, backwards, sideways, or diagonally. The idea is to recreate the natural trajectories of a human moving through a crowd while enabling you to rapidly move sideways or diagonally to avoid sudden obstacles. Want to turn? Just dab your foot to twirl around the wheel's axis. The whole thing feels freakishly natural, as if you were born with an omnidirectional wheel attached to your butt.

It's that naturalness that makes the U3-X unique. Unlike the Segway, there's virtually no learning curve for beyond remembering to relax and not overdo it. And unlike Dean Kamen's two-wheeled folly, the U3-X allows you to move naturally and easily, traveling though and interacting with your environment in a fluid, organic way.

Other than all the pointing and staring, riding the U3-X around Times Square didn't feel odd. It felt normal. That's what makes the little silver Honda so special — it's the first mobility device that feels and operates like a natural extension of your body.

Photography credit: Michael Ginsburg