One such gadget that comes to mind is a breath-analyzer the driver must blow into in order to be able to start the car. If the analyzer senses alcohol, the starter shuts off and the driver can't start the car.
Nissan Motor Co. has come up with something that incorporates the use of its CARWINGS navigation system. It will display "Do Not Drive After Drinking!" every time the ignition is turned on during evening hours to remind the driver of the dangers of driving drunk. The warning will only be on Nissan vehicles sold in Japan.
Our take? Nice thought. But where's the prevention. Heck, the driver could be too drunk to read the message. A more active system would be more appropriate, wouldn't you say?