Behold, the Copenhagen Wheel.
Now, this is pretty awesome on a few levels. Firstly, as the video explains, it attaches easily to almost any bicycle and stores energy from braking to help you when you need it, similar to what the Prius does. That makes biking easier for hilly places, like Seattle. Now, that’s cool and all but I’ve seen that before. However, it gets better.
The device also includes sensors for speed, effort, and environmental conditions. These can be transmitted to your smart-phone so that you can regulate your biking effort (e.g. tell the device to use the stored energy to make the ride easier/faster), see real-time data on relevant conditions (e.g. traffic, air quality, etc), and you can opt to share data that your bike picks up. As they say in the video, it basically turns every bike into a mobile weather station which shares important information with the city and other cyclists.
So, aside from making biking - an already very green alternative - a bit easier no matter where you live, it also makes your riding “smarter” (e.g. can make it more into a personal training program) and also help monitor conditions, which can be very useful for city initiatives which require data on things like air quality or road quality. (Could you imagine how popular and useful this would be for a city bike program?!)
All in all, this seems like quite the win, though perhaps still a bit expensive.
(And a hat tip to thegreenurbanist.)