A good physical security rabbit hole is Deviant Ollam: https://www.youtube.com/deviantollam

This is a great writeup, I did something similar to sneak into friends dorms in college! Security through obscurity in action, the Crypto-1 algorithm was reverse engineered by literally looking at the hardware implementation on silicon: https://www.usenix.org/legacy/event/sec08/tech/full_papers/n...