As an example, let’s consider the AND gate (the others are OR, NOT, NAND, NOR, XOR and XNOR ... but there are many ways to implement them. Using relays is one of them, and you can literally ...

Using an old chessboard, eyelets, rings, weights, and string, [Alex] has designed a system that can show off all of the logic gates. This includes: NOT, BUFFER, NAND, AND, OR, NOR, XOR ...

A technical paper titled “Logic-in-Memory Operation of Ternary NAND/NOR Universal Logic Gates using Double-Gated Feedback Field-Effect Transistors” was published by researchers at Korea University.