Here is a Web site by a guy who designed working versions of all the basic logic gates, that is the NOT, OR, NOR, AND, and NAND gates, with Lego blocks.

NAND gates are significant because any Boolean function (AND, OR, NOT, XOR, XNOR), which play a basic role in the design of computer chips, can be implemented by using a combination of NAND gates.

NAND and NOR gates demonstrated by spin waves using magnetic oxidesSpin waves can be applied to low-power multi-input-multi-output logic gates based on its wave functionality realized without electron ...

This CMOS two-input combination NAND/NOR gate is a three-input, fourpin logic gate. A p-channel enhancementtype MOSFET (Q1) and an n-channel enhancement-type MOSFET (Q4) form one complementary ...