Physical Computing, sensors walk (ass. 1)
noun \ˈsen-ˌsȯr, ˈsen(t)-sər\
1: a device that responds to a physical stimulus (as heat, light, sound, pressure, magnetism, or a particular motion) and transmits a resulting impulse (as for measurement or operating a control)
Here are some sensors I saw this weekend
These and some others I saw include a sliding door, an X-Ray, a help line (for someone to dial up and get help at the airport), a button to press for the flight attendant to come help, an A/C, hand driers, light switches, a car (including many sensors)…and more.