The dyed Chicago River doubles as a perfect green screen in this hilarious video

The Chicago River was dyed green for St. Patrick's day. And for the memes.  Every year, Tom Rowan dyes the Chicago River in honor of St. Patrick's day. It's a tradition that started in the 1960s when the mayor decided he wanted to do something festive for the holiday. The vivid color is the result of 40 pounds of orange "Leprechaun Dust" that turns electric green upon hitting the water.  It just so happens to be the same green hue used for green screen purposes.  Twitter user Donnacha Kenny decided to see what kind of special effects magic he could whip up by turning the river itself into a green screen. Kenny transformed real footage of the river into several different scenes including flowing hot lava and a clip from Star Wars.  Read more...More about Twitter, Chicago, Viral Videos, Green Screen, and Chicago River