Here's a new way to capture the attention of kids walking through the aisles at your local grocery store: cereal boxes that are filled with flashing graphics, text, and photos, all blinking on miniature flat screens instead of the traditional ink-printed images now used. Electronics maker Siemens says it can make it happen with a new, paper-thin electronic-display technology that is so cheap it could replace conventional labels on disposable packaging, from milk cartons to boxes of Cheerios. Siemens says the technology consists of a polymer-based photochromic material that is capable of displaying digital text and images when prodded by an electrochemical reaction powered by a low-voltage charge. When the electric charge is no longer applied, the chemical reaction is reversed, and the electronic ink is no longer visible--which is how a flashing effect is created. The power source is based on commercially available, ultra-thin batteries. Electronic memory strips store the images. The display resembles a calculator screen, except the monitor is attached to a flexible, plastic-coated card. Pressing a button on the card causes monochromatic digital text to light up; when the button is released, the text vanishes.