You want an e-bike, but still like your old bike buddy, this startup has a great solution.
CLIP is a portable attachment that can turn any bicycle into an e-bike. The gadget is set with a 450W motor and is designed to aid commuters with the toughest stretch of their cycle into work. The attachment is portable, so commuters can easily hide their secret booster, which can be recharged in less than 15 minutes for another one hour of power.
The principle is pretty simple, clip it to your bike, you ride then unclip and recharge it at work or home, check out the CLIP website for additional information.