This is completely different from the stuff I usually post about. Normally I’d just Twitter these, but this one’s too good to be lost in the middle of the thousands of Twitter updates I’ve posted.
I was doing some research on early calculators, and I found first a YouTube video, then a Web site describing a marble-based binary adding machine.
The video is just over three and one-half minutes and is a rather thorough demonstration of the machine the author built (which can tally results up to 63 or six bits), including an intentional overflow.
To say I was awe-struck is an understatement. This is probably one of the ultimate geek toys.