The Grecian Computer, a truly diabolical brainteaser, is a test of visualization and problem solving skills. Based on an ancient device thought to predict astronomical positions is rated 5 out of 5 on the difficulty scale. Crafted from wood and designed to challenge even the sharpest minds, this puzzle requires you to spin layered gears until each column adds up to 42 simultaneously. This puzzle is made by Project Genius, a U.S. based, woman-owned company with a dedicated work program for young adults with autism. Puzzle is new in box, I pulled it out to photograph.