mollyhackit writes "Here's a how-to guide for building a keyless entry that uses color identification instead of numbers. All eight buttons are initially blue; as you press the individual buttons they change color. Cycle the colors to your particular pattern, and you're in. This lock obviously wasn't designed for high security use since anyone in the same room would be able to see you and your amazing technicolor dream lock's pattern; it's just a fun project and will keep the youngins out of your workshop (timer prevents brute forcing). The RGB buttons are monome clones from hobby shop Sparkfun."