To me this is far more impressive than any of the other stuff posted here. It's actually doing it rather than talking about it or faking the first 99.9% of it.
Did he do his own etching? I'd say buying blank wafers would be a perfectly reasonable place to start, but if you're buying printed wafers, then you might as well buy the whole chip.
https://www.youtube.com/watch?v=w_znRopGtbE
https://www.youtube.com/watch?v=-Qph8BNrnLY