This LED watch design is a challenge to your eyesight and to everybody else’s. At first glance, all you will see on its screen is a series of green and black lines appearing to form an undecipherable maze. Lying within the maze, however, is a combination of numbers that will tell you what time of the day it is. If you can train your eyes to read among all those lines, then you are an optical illusion genius! If you can’t however, which just makes you an average mortal being like most of us are, then you can press the button on the watch and the numbers will emerge out of the green and black lines to tell you the time in plain sight.