It's the most wonderful time of year. The air is crisp, yards are decorated with lights and inflatable figures, fir trees are on sale at the hardware stores, television commercials are laced with holiday cheer and jingle bells -- that's right, it's Halloween. Last year for Halloween I decided to create an Arduino-based electronic scare device to creep out our trick or treaters. (An Arduino is a low-cost microcontroller that is easily programmable to do all kinds of cool stuff