Old story: Websites that know what other sites you visited on the internet and show you ads that fit the best guess at your interests.

New story: Billboards that know where you have been driving or retail stores you have visited and change their message to fit the best guess at your interests.

Clear Channel Outdoor, one of the world’s biggest sign companies, announced RADAR in March, a partnership with three companies (AT&T, Placed and PlaceIQ) that track the movements of cell phone owners, crunch the data and predict the interests of the drivers passing by any particular location. Clear Channel feeds that data into its system of roadside digital billboards that can change their messages as easily as a website can change its ads.

Clear Channel says the data is anonymous and its interest is treating passing drivers as a collective audience, not individuals to target.

Not anonymous enough for Senator Chuck Schumer of New York who called RADAR, “spying billboards”.

“A person’s cellphone should not become a James Bond-like personal tracking device for a corporation to gather information about consumers without their consent,” Schumer added. He wants the Federal Trade Commission to investigate.

One of the partners, Placed, would dispute Schumer’s point about consent. According to the Placed website, its panel of consumers give their consent to install the tracking app in their mobile phones in exchange for gift cards and other incentives.

But no driver gave consent to be the target of this spying billboard, recently reported by the Chicago Tribune. Promoting the Chevy Malibu, the sign mounted a camera that photographed the grills of passing cars, recognized the makes, and changed to message to read something like “More Safety Features Than Your Nissan Altima” in enough time for the Nissan driver to see it.

Hmmm. Stick a camera with facial recognition software on a billboard and things could get really personal.