Gyrobike's Gyrowheel stabilizes a kid's first bike without the training wheels
by Paul Miller posted Oct 3rd 2009 at Engadget
Being the fine physical specimens that we are, even from an early age, we of course had little trouble learning how to ride a bike without external help, but we're sure **some hapless child out there will welcome the Gyrowheel as salvation from the embarrassment of training wheels
The 12-inch wheel (a 16-inch version is in the works) replaces a standard front tire and has an adjustable-speed spinning disc inside, powered by a rechargeable battery. The idea is that you get the kid started on a high stability setting, and step them down until they're not using the gyro at all.
It goes on sale this December and should retail for around $100.