Superpedestrian, a Boston based startup, is literally reinventing the wheel! Their product, The Copenhagen Wheel, replaces a standard rear bicycle wheel with a special wheel with a motor and a lithium battery. The wheel captures energy from braking and pedaling backwards, and uses that energy to assist the rider when sensors perceive their level of effort has increased. As a result, hills should feel no different than flat terrain. Their hope is to encourage more people to commute via bicycle.