Since I use my bike as a commuter vehicle for 90-95% of it's duty, I've also thought about buying a new-erish 600 sportbike with a bad engine, and figuring out how to make it electric. I wound't be worried about distance so much as making it reliable and functional. I think an electric bike would kick ass! Especially if you geared it all for in-town torque with 80-90 mph max speed, and not worrying about a super long range.