This train leaves trails of Laser graffiti
It all started out when Aaron Koblin and Ben Tricklebank found a powerful RGB laser on Ebay for 600 bucks and decided to point it at the canyon walls outside LA. Unfortunately, the light show scared the whits out of an elderly man who happened to also be in the area (the middle of nowhere, to be precise).
Though the display was mistaken for an alien landing, the guys were able to successfully create temporary laser graffiti to be caught with long exposure. What was the next logical step after lighting up the canyon walls? Attach the contraption to a train and light up the tracks across America! And so, Light Echoes was created.