Solowheel

"A next-gen Segway in unicycle form
Like a stripped-down Segway, Inventist's new Solowheel is geared for the mobile urbanite. The "self-balancing electric unicycle" operates through gyroscopic technology, which a 1000-watt rechargeable lithium-ion battery powers. On a full charge (which takes about 45 minutes), the Solowheel lasts two hours—but the battery actually recaptures energy when going downhill.
Weighing only 20 pounds and consisting of little more than a simple wheel with a fold-up foot platform on either side, you can easily throw it in your backpack or briefcase once you reach your destination, or carry it by its convenient handle."
via:coolhunting.com