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9 of the craziest things made of wood

By: Shea Gunther on Nov. 22, 2010, 12:44 p.m.
wooden adding machine that uses marbles

Photo: YouTube

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You wouldn't take this calculator with you to a math test, but it does a fair job of adding up numbers — if you don't mind entering your calculations in binary. This calculator uses marbles and switches to add the numbers together.