The Wall Street Journal has an interesting article on the technology behind haptics, derived from the Greek word meaning "to touch".

"A group of science museums in the US is showing off one form of the technology. The system, dubbed the Internet Arm Wrestling Challenge, uses aluminum arms and hands connected by a series of rods and gears to computer servers linked to the Internet.

Visitors looking for a test of strength sit in front of a touch-screen monitor and ask the computer to look for a potential opponent at another museum. If one is available, his or her picture appears on the screen via streaming Internet video, the two wrestlers grip the metal hands and the computer starts the contest".