Justin from ebikes.ca has had a traditional type uni cycle with an electric motor on it for sometime
full build log on Endless Sphere forum
EDIT: according to the nets most reliable reference :-P Wikipedia your build is a -> Impossible wheel (BC wheel):
a wheel with pegs or metal plates connected to the axle for the rider to stand on. These wheels are for coasting and jumping. A purist form of unicycle, without cranks.