10 Fuel-saving Device Hoaxes

For as long as we've complained about gas prices, there's been an army of inventors offering devices to stretch our mileage further. But which ones work and which are hoaxes?

Source: http://feeds.howstuffworks.com/~r/DailyStuff/~3/krYEj_5vpH8/10-fuel-saving-device-hoaxes.htm

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