I setup an Electra Townie with a BD-36 electric hub motor from We R Electrified for a handicapped friend. It works exceptionally well. He does a 6-mile commute to work one way and he charges it at work for the return trip. He does not pedal or help it at all. He also runs the throttle wide open on that 6-mile trip.
http://www.werelectrified.com/unibikekit.html