Incredible machines built with LEGO!

'' Machines have long been used to ease repetitive labor. Some machines eased the labor of calculation; watches, orrerys, calculators, difference engines, etc. Gears were the workhorse of this age reaching the zenith during the late 19th century only to decline as they were replaced with transisters for most computation.
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Babbage Difference Engine made with LEGO

This is the 3rd generation of Babbage Difference Engine made with LEGO. It is modeled after Babbages Difference Engine #1. The 3rd generation operates five times faster than the 2nd generation.

This machine can evaluate polynomials of the form Ax^2 + Bx + C for x=0, 1, 2, …n with 3 digit results.

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Antikythera Mechanism (Eclipse Predictor) made with LEGO

This machine, modeled after the ancient Greek original, can calulate the date and time of solar and lunar eclipses over a hundred year period.

It is an analog computer with over 100 gears and 7 differential gearboxes. It is accurate to a day or two over it's range.

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Also this project is very interesting, showing how make a working 7-segment display with lego technic [video]