The XT was specifically developed for stability, comfort, and performance on rough and uneven terrain. Its low-pressure tires smooth the ride on bumpy surfaces and minimize trail impact, while the transporter's wider track will prove more stable on uneven ground than the original Segway HT. The XT's software has been modified to support the new tire size and to improve handling, with inertial sensors that continually monitor a rider's position relative to gravity. This allows the XT to adjust for changes in terrain while keeping you upright.

The increased energy capacity of the XT's lithium-ion batteries supports the XT's demands while still providing a 10-mile off-pavement range (depending on the exact terrain and your riding style and payload). And, as with its other transporters, Segway designed the XT with safety in mind, so it's engineered to turn in place on a 0-degree radius just like a person would, permitting unobtrusive negotiation of sidewalks, elevators, trains, supermarkets, and other venues. You'll never have to worry about finding yourself in a space too tight to turn around in.

Between the bronze sport striping on the black fenders and the unit's polished-aluminum wheels, the Segway XT is a machine of rugged beauty. The XT's sturdy fenders were designed to protect you from debris, even during leaning turns. Conveniently, their aluminum frames have built-in lift handles to help you (and a friend) load the 100-pound transporter in and out of a vehicle.

The gyroscope, or "gyro," provides the heart of the Segway human transporter's self-balancing technology. What Segway calls "dynamic stabilization" is actually a combination of gyroscopes (or "angular rate sensors") and tilt sensors working together with state-of-the-art computers and motors to keep the transporter balanced when you're on it. This technology checks your center of gravity 100 times each second and instantly responds to changes in your body's position--so there's no need for brakes or an accelerator. Truly. Lean forward and you go forward. Lean back and you move backward. Straighten up and you stop. That's it.

Located in the center of the XT's riding platform, the balance-sensor assembly is a cube 3 inches on a side that's packed with 5 gyroscopes and 2 tilt sensors all operating independently to gather information about the platform's position--and to check in with one another to make sure each is working correctly.

In fact, the XT (like other Segway transporters) sports no less than 5 redundant subsystems, each of which allows you to maintain control of the device in the unlikely event of a component failure. If something goes wrong with any one of systems, there's a twin that will continue to work and bring you safely to a stop. The Segway XT will also warn you by beeping, vibrating, and flashing (discreetly, of course).

Each of the transporter's keys holds a unique, 64-bit security code that your machine won't start without. These special keys also let you select different turning rates and transport speeds. Meanwhile, a center-mounted backlit LCD tells you what you need to know about your transporter--like whether it's ready to roll and how much charge it's got left.

Each of the XT's 2 batteries contains a circuit board that continually monitors its own temperature and voltage. Through smart charging technology, the batteries actually choose the right charge rate based on temperature, voltage, and power level when plugged in. And get this: a full charge will cost you only about 10 to 20 cents, giving you literally hundreds of miles to the proverbial gallon.