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Copenhagen Wheel

Long commutes, hilly rides, and difficult terrain may have you reconsidering the whole biking to work thing — but before you go replacing your bike with some expensive electric vehicle, consider the Copenhagen Wheel ($800). This simple device replaces the rear wheel of your standard bicycle, giving you the extra boost of power you need to overcome any commuting obstacle. With a built-in motor, it will help you tackle hills, or just show up to work a little less sweaty. And with wireless connectivity, and the accompanying app, you can tailor your ride to fit your needs, or just keep track of all the good you're doing for your body while biking instead of driving.

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