Cited as a reference
Harry Porter's Relay Computer
Why people recommend it
A demonstration of a computer built entirely from relays, linked both as a serious example of relay logic and as a tongue in cheek extreme.
Watch for: Inspiration rather than a build guide
In their words
Tell your boss that you will provide this and he/she can program one of the relays to yield the desired results.
jonk on electronics.stackexchange.com, Jun 2020. CC BY-SA.
If you liked this
Programming my 8-bit breadboard computer
Hidden gem