Helpful details from Focus Designs' FAQ on the SBU:
Is it easy to ride?
It is much easier to learn compared to a conventional unicycle. The average user needs only twenty minutes to two hours of practice before he/she can have a decent first ride. The average is about 45 minutes of practice. The SBU is a rider-assist machine, a combination of the rider’s balance and SBU control.
How fast does it go?
An SBU falling vertically through the air will accelerate at an amazing rate of 32 feet per second per second until it reaches its terminal velocity of 193MPH. (We do not recommend traveling this fast.) On level ground and full charge we say it can go 10MPH depending on riders guts (mentally and physically).
How far can I go on a single charge?
About 10 miles on a single charge, or forever if traveling vertically in a bottomless pit.
SF fans get quite a kick from the SBU, having fond memories of reading about Robert Heinlein's tumblebug from his 1940 novella The Roads Must Roll:
Gaines and Harvey mounted tumblebugs, and kept abreast of the Cadet Captain, some twenty-five yards behind the leading wave. It had been a long time since the Chief Engineer had ridden one of these silly-looking little vehicles, and he felt awkward. A tumblebug does not give a man dignity, since it is about the size and shape of a kitchen stool, gyro-stabilized on a single wheel.
(Read more about (and see a picture of) Heinlein's tumblebug)
Thanks to Daniel Wood for pointing out this enjoyable video about the SBU from Focus Designs.
Scroll down for more stories in the same category. (Story submitted 12/22/2009)