Ian Stewart's article in Scientific American was based on "Train Sets" by Adam Chalcraft and Michael Greene (Eureka 53, pp. 5–12), which also provides the basis of the Duplo constructions. (But note that Duplo has linked points as well as sprung and lazy points, which allows for more compact constructions.)
Somewhat related to computation and train tracks (though using train tracks for binary state is really awesome!):
"Introductions to Monads" are a dime a dozen, but this one, which uses train track analogies (a monad is just an adapter that changes a noncomposable function into a composable segment for a path), was the one that got the entire concept to click for me. Highly recommended.
On of my on-the-list-when-i-get-old project: build a lego train system with HD camera in the cockpit that users can visit my website and navigate said train online :) something tells me there is a buck or two in such project :)
Desmond Bagley's novel "The Enemy" features a model train set whose layout/timetable was used by the ex Russian spy also a genius, to encode his research and leave for posterity. Haven't read for years but enjoyed it!
“A Subway Named Turing”
Subscription-required link : https://www.nature.com/scientificamerican/journal/v271/n3/pd...
Love the closing line (as the train passengers discussing the concept of train logic circuits realise they haven’t come to a station in awhile):
>“This isn't any touring machine," the guard said indignantly. "This is a personnel commuter, buddy." >At least, I think that's what he said.