Here is a special monowheel that brings back memories from the 2008 Beijing Olympics, if you actually cared enough to follow it. Its spinner outer ring has bright LEDs. The outer wheel rotates as you pedal. You can steer this by leaning in your desired direction. Braking happens with your feet. You can put on a cool light show with this at night. The monowheel does have a 1800 mAh battery for those lights.
The monovelo is made from steel and ABS plastic. It can accommodate users up to 6′ 2″ and 230 lbs. Be ready to break the bank to get one of these.