Digi-Comp II: A Mechanical Computer

The folks at EvilMadScientist.com bring you a giant working replica of the Digi-Comp II, a 60s-era build-it-yourself computer kit:

http://www.evilmadscientist.com/article.php/dciivid

After the switches are initialized to choose the operation, the machine channels a stream of pool balls through various binary gates to effect addition, multiplication, and other basic mathematical and computational procedures.   For more information, check out www.digi-compii.com.

As a pure math person, I never fully appreciated these mechanical computers.  But after seeing things like the Digi-Comp, cam-based mathematics, and various mechanical calculators, I’m developing a genuine respect for them