Traffic Lights by Flash and Math - A very challenging variation and extension of the classic "Lights Out" puzzle. Can you get all the lights to be green? Clicking on a light will change its color, but also the color of all of the neighbor lights attached to it. The lights cycle through green, yellow, and red, just like a traffic light. The puzzles are made from a grid of lights (of varying sizes depending on the settings) which are connected in randomized configurations. Complete source code is available for download from flashandmath.com.