It looks like technology is making a perfectly good insult obsolete.
From an Article in The Christian Science Monitor...
Another modification to the built environment is the carbon fiber-reinforced concrete of Deborah Chung, a materials scientist at the State University of New York at Buffalo. By running an electrical current through concrete, Dr. Chung says, tiny deformations caused by minute pressures can be detected. "You can monitor room occupancy in real-time, controlling lighting, ventilation, and cooling in relation to how many people are there," says Chung.
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Other things she suggests elsewhere (Google using "Deborah Chung concrete") are weighing trucks as they pass by at highway speeds, monitoring roads/bridge surfaces, de-icing, etc. .