The Data Dentata is a simple tele-touch machine created in 1992 by robotics expert and artist Ken Goldberg with the help of AI guru Richard Wallace. Its purpose is to allow two people to hold hands remotely. It's official name is the Datamitt, but the reluctance of some to have their hand squeezed in the machine led it to be nicknamed the Data Dentata, a name that seems to have stuck and by which artist Goldberg typically refers to it.
The Data Dentata was demonstrated publicly for the first time at SIGGRAPH '93, an annual computer graphics conference. Two metal tubes were equipped with one-bit touch sensors and haptic actuators, then connected over a simple telephone line. One of these was stationed at SIGGRAPH in Anaheim, the other at New York University. Users at both stations were able to squeeze their partner's hand at the other end of the connection, and vice versa. The squeeze/no squeeze feedback was binary, with no pressure gradation, yet people still responded strongly, often attesting to a high sense of the other person's presence.
A paper by John Canny and Eric Paulos reports an interesting anecdote:
Richard Wallace manned the NYU station most of the time but secretly took a break by hotwiring his sensor and actuator to reflect the LA signal back to the LA apparatus. One of LA participants using the machine during this time said she felt very close to the person in NY she was interacting with. In fact, the apparatus was simply reflecting her own squeezes back to her, with some delay—a perfectly reasonable behavior for a real stranger to do.
Philosopher Andy Clark, who is concerned with the ways our minds and bodies can extend themselves beyond the confines of "the biological skin bag", has used the Data Dentata as an example of embodiment-at-a-distance.
Goldberg has a picture of the Data Dentata hosted on his website.