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Watching a single LED blink is potentially hypnotizing, even if it blinks at a fixed rate with a fixed duty cycle. That’s promising for a set of three LEDs flashing in quasi random order with a constantly varying duty cycle. An out-of-body experience? Nirvana? Kobain? Maybe you just fall asleep. Anyway, the simple circuit presented in this .POST article will flash three LEDs in such a way that you can look at them for hours without ever getting bored.