The makers of a 'revolutionary' mode of transport are praying it will fly out of the shops, writes Paul Cullen.
It looks like a cross between a lawnmower and a pogo stick, and it will shortly be coming down a pavement near you. It is, its promoters claim, the most revolutionary high-tech invention since the PC or the Internet; detractors say it will go the way of Guinness Light.
"It" is the Segway, described as the world's first electric, self-balancing transportation device. Developed at a cost of $100 million (€93 million) and kept closely under wraps to bring expectations to bursting point, this latest attempt to crack the nut of electric transport promises to be one of the year's talking points, if nothing else.
The Segway is two wheels connected by a platform on which the user stands and grips a waist-height handle. Between the wheels lies the invention's secret heart, a complex array of hardware and software that mimics the human body's ability to maintain balance.
So lean forward and the Segway moves forward. Think about stopping, straightening your back, and it stops. Lean back and it moves in reverse. Movement is effected by a series of gyroscopes and tilt sensors, which monitor a user's centre of gravity about 100 times a second.
The handle only really comes into play for turning, which the Segway does on the proverbial sixpence. Maximum speed is about 12.5mph.
Range varies according to the model, but you can expect to travel up to 16 miles before needing a recharge.
The challenge of creating a practical, affordable form of electric transportation has produced many false dawns, but the Segway looks promising. It has no engine, no throttle, no gear lever and no steering wheel. It can carry its rider - passenger? driver? - for a full day on 10 cents' worth of mains electricity.
Its inventor, Dean Kamen, says the device works equally well indoors and outdoors; he says it's sturdy enough to cross grass and even snow. He claims the Segway will have far-reaching benefits, including the creation of more liveable communities.
"In time, the Segway will lead to a reconfiguration of the way communities are built by significantly extending people's walking zones, thereby enabling better use of space and the transportation infrastructure. It will enable people to make better use of their time, interact with people more easily and, ultimately, live better lives."
This writer would love to be able to confirm the wondrous benefits of the Segway, but the nearest he got to doing so on a recent trip to California was to stand on a gyroscope-less model in the Tech Museum of Innovation, in San Jose.
The invention has been kept a closely-guarded secret, with advance sales possible only through Amazon.com from the start of this month.
But even a cursory inspection of the Segway reveals some drawbacks. It is heavy - too heavy to push up stairs or kerbs. It is too slow to travel on the road yet too large and fast to safely use on many pavements. You wonder how easy it would be to use and how long it would last on Ireland's cracked, uneven and car-strewn pavements.
Safety is clearly a concern for the inventor and his team, who insist that purchasers go on a training course before taking home their new toy. Nonetheless, four Californian cities have pre-emptively banned the Segway from their streets.
Then there's the issue of price - about $5,000 (€4,700) initially in the US, or the cost of two petrol-fuelled scooters. There's also a danger that the very people who most need to take exercise will be the ones to stop walking and start standing on a Segway.
Initial uses will probably be indoors; for example, in large factories, such as Amazon.com's book warehouses). The US Postal Service and National Park Service are testing the device, as are a number of industrial corporations.
But if the Segway really is as good as the hype, the public will make up its own mind and Kamen may soon be selling his targeted 40,000 Segways a month.
In such a case, you might see how cities could be redesigned around this latest entrant on the roads.
Until then, though, you might think of walking to your destination.