There are several, but this one is my favorite: https://monster6502.com/ https://monster6502.com/ This was made from a netlist that was reverse engineered fro

There are several, but this one is my favorite: https://monster6502.com/ https://monster6502.com/ This was made from a netlist that was reverse engineered from microscope images of the 6502 die, and I think uses a roughly similar die layout. It uses discrete transistors and a handful of transistor array ICs (because you need an exposed "body" pin in order to make a functional pass gate).