Where else but Sacramento, California, would smart billboards electronically scan the airwaves to detect which radio stations approaching motorists are tuned into?

According to the driver’s station-of-choice, a computer then selects the most appropriate ad for the billboard to display.

It is not known what happens on an eight-lane highway during rush hour when the scanner homes in simultaneously on several hundred oncoming autos.

Data sourced from: Auto Express (USA); additional content by WARC staff