Imagine a birthday card whose candles light when you pick it up then go out when you blow on them. That is completely possible using a new technique for printing electrical circuits developed by Kate Stone, founder of Novalia, a printing firm based in Cambridge, UK. This new technique turns the normal process for creating a printed circuit on its head. In her method a designer first creates an ordinary image on the page. Then an electronics engineer uses special graphics software to superimpose a circuit on the image, following the lines of the original design. The circuit can incorporate LED lights, motion sensors, microphones, or touch sensors. A controller the size of a postage stamp is then placed behind the image. This technique allows almost any image to become animated right on the page. It could be used to produce animated childrens' books that react to their touch and voice.Imagine all the possibilities this could open up! What would you create?Original article at New Scientist magazine.