I don't know how new these kits are, but I haven't seen them before.
http://www.batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=4556These are pretty neat, just remove your front wheel and replace it with a wheel that has a brushless DC motor in it. Add the carrier and pack for the batteries and controller and you are just about ready to roll.
Has anyone tried one of these?
Scott...