Cheap acoustic sensors make surfaces interactive

New Scientist has an article on turning any surface into a touch screen using small piezoelectric sensors to sense surface vibrations -

_"A series of acoustic sensors that turn any surface into a touch-sensitive computer interface have been developed by European researchers.

Two or more sensors are attached around the edges of the surface. These pinpoint the position of a finger, or another touching object, by tracking minute vibrations. This allows them to create a virtual touchpad, or keyboard, on any table or wall."_ [via] - Link.

(Via MAKE Magazine.)