An ad firm in London has been using embedded technology in trash cans to track people's smartphones in the city's financial district.

The City of London Corporation has demanded that the Renew ad firm "pull the plug on the program, which captures smartphones' serial numbers and analyzes signal strength to follow people up and down the street."

The AP story adds:

[I]f a company could see that a certain smartphone user spent 20 minutes in a McDonald's every day, it could approach Burger King about airing an ad on the bin's video display whenever that user walks by at lunchtime. Or it could target its commercials in real time by distinguishing between people who work in the area and visiting tourists.

The prospect drew comparisons to the creepy "Good evening, John Anderton" ads from the Tom Cruise thriller "Minority Report."

(Image: AP)