clipped from: www.techeblog.com 
The Philips Drag & Draw installation basically "enables the user to paint via laser beams -- simply wave the wand over the laser projection bucket, then use it to draw on any wall or surface."
University researcher Daisuke Iwai has developed a new technology which allows people to paint using thermal vision technology. This system "can detect temperature change regions on a sensing surface as touch regions when objects hotter or colder than the surface touch it."
At first glance, it looks like your standard brush, but upon closer inspection you'll find integrated LEDs, touch sensors, and a camera. The I/O Brush basically "lifts up and captures photons", allowing artists to draw with "special ink" picked up from their immediate environment.