Complete with tapedrive and typewriter. Operates at around 0.12Mhz, has roughly 2K of memory and each tape holds around 360K. It has 200 tubes, compared to hundreds of millions of transistors in a modern PC.

The thing that caught my eye about this is the typewriter. It's a Flexowriter by Singer. I bought one when I was 15 (it was 20+ years old by then). It was basically a typewriter that could read and write punched tape. I used it to print receipts for customers on my paper-route, and I was the shizits among my fellow paperboys.

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Andrew Carol built a difference machine from Legos. The Difference Machine was invented by Charles Babbage, and uses Newton's method of differences to evaluate a polynomial.

This lego version can compute 2nd or 3rd order polynomials to 3 or 4 digits.

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Play chess against the computer and see what the computer's thinking. See waves of influence between turns, and while the computer is thinking, see which moves the computer is pondering (as pictured here).

It takes forever to make moves and it isn't a very good player (it doesn't know any openings for one thing, and doesn't seem to understand basic development concepts), but this is by design so that every move is "thought through" so you can see the thinking visuals.

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Peter Klausler used evolutionary software techniques to devise the perfect computer keyboard layout, and came to the conclusion (so far) that he couldn't beat Dvorak.

Once upon a time, I forced myself to switch to Dvorak, but the switch was painful. Initally, it slowed me down substantially for the few weeks while I was switching (I type around 80+ wpm on qwerty, so going back to square one is a dramatic impact). But the bigger problem was that once I learned it, it was difficult to type on other peoples keyboards. So, I switched back.

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