My 9 year old son used Mindstorms for a recent school science project. He built a computerized house that he programmed to react to light (morning) and darkness (night). When it was night, the house automatically rolled down the shades, and turned on the lights for a specified amount of time. In the morning, the shades would roll up and an alarm clock would ring. He even programmed a snooze alarm that would roll down the shades and shut off the arm for a short time, then go off again.