My boss is completely in love with conductive ink. What exactly is it, and why would I ever use it in a trade show booth?

Conductive ink is a liquid that allows a figure drawn with it to transmit electricity. Comprising four main components (a solvent, a conductive material, a polymer binder, and an electrical source), it can be applied to a surprising range of materials, including plastic, plaster, paper, wood, and even cotton fabric, effectively turning the surfaces of these substrates into electronic devices. When activated, the materials might play a song, illuminate an illustration, or even warm the interior of a jacket. While applications are almost endless in the exhibiting world, exhibitors have recently turned to conductive ink to enhance T-shirts, augment graphics, and improve wayfinding – crafting, for example, a lighted pathway along a wall that interacts with an attendee's touch.