Odds: 4 to 1 Like the Siafu, the ZEN is specifically designed for the visually impaired. It is comprised of hardware called the "Sandbox PC" and a so-called ZEN edition operating system. The two work together to create a computing environment that can be used with your eyes closed. The Sandbox PC features Active Surface, an electronic surface that can take on different physical shapes and be manipulated by the user. You can read Braille text on it and make out windows, icons, and different textures. All input is made by touch--you can press into the surface, or scratch it with your fingers.