Chris Owens, an enterprising design student from North Carolina State University, created a shelf that's lit from beneath by LEDs. Pressure-sensitive switches embedded in the shelf turn on those lights when you place an object on them. Take a look at the video to see the design prototype in action.
Wouldn't this be great to have a bar made of these pressure-sensitive lights? The bartender puts your drink in front of you and the bar lights up. Neat.
Illume - LED Display Shelf [Tech E Blog]