An old article by me at javaranch journal
Like wind-mill.. We can try to make use of the pressure that occurs when you are driving a car or sitting in an open bus. In India some of the village buses got open windows, normally buses drive at 50km/h which inturn forces lot of air in your face, we can use this wind power to rotate a set of fan blade like plates and turn that roatation force in to motor energy. This motor energy can create DC electricity which can be used to charge your discman battery or cell phone battery.
This idea can also be used while using car escp when you are driving from LA to Texas or CA.
Late back Chinese-Taiwainese introduced a kind of self chargeble fan with batteries in it, this fans had a larger market swipe in north India once. The same idea can be appiled for this.
May have good market in Asian and African countries.