In most elevators installed since the early 1990s, the “close door” button has no effect. Otis Elevator engineers confirmed the fact to the Wall Street Journal in 2003.

Similarly, many office thermostats are dummies, designed to give workers the illusion of control. “You just get tired of dealing with them and you screw in a cheap thermostat,” said Illinois HVAC specialist Richard Dawson. “Guess what? They quit calling you.”

In 2004 the New York Times reported that more than 2,500 of the 3,250 “walk” buttons in New York intersections do nothing. “The city deactivated most of the pedestrian buttons long ago with the emergence of computer-controlled traffic signals, even as an unwitting public continued to push on.”

(Thanks, Tad.)