Electric hub for commuting?

Check out goldenmotor.com.

I have noticed though, that hall-effect DC motors have some drag when pedaling (not just when the hub is charging the batteries. when it's off.). I don't know if this is a drawback for you but I planned to power to school or work then pedal back; it would be too much of a workout. I basically sold my unit on ebay.

Lead-acid batteries: cheap, heavy, you have to charge them as soon as you're off the bike or they're toast, much less range in the cold.

Lithium or NiMH: pricey but lighter, charge them when you want, less sensitive to cold, small and light enough to be carried on your person, so as to keep them warm.

Also, there is a possibility, however slight, that the cops will jerk you around. I think an e-bike which can go over 20 MPH counts as a moped. Illinois wanted me to register mine as a motorized pedacycle, i.e. moped, because the Goldenmotor kits can do 24mph. (I emailed the state police)

JFTR I bet no one would give a [censored] as long as you were responsible, but who knows.