AnimalCrossingPerson
Please respect GDPR
Seems no-one else has posted this here, so I will. It's a very technical read, so some may find it interesting, and others not:
https://jamchamb.github.io/2018/07/11/animal-crossing-nes-emulator-hacks.html
Long story short, the standard NES item in-game checks the memory card for NES ROMs. Of course, it never finds any since Nintendo didn't utilise this feature. With some trickery, it's possible to use this feature to get custom NES ROMs loaded and even exploit this to execute arbitrary code in-game without having to modify the game itself.
https://jamchamb.github.io/2018/07/11/animal-crossing-nes-emulator-hacks.html
Long story short, the standard NES item in-game checks the memory card for NES ROMs. Of course, it never finds any since Nintendo didn't utilise this feature. With some trickery, it's possible to use this feature to get custom NES ROMs loaded and even exploit this to execute arbitrary code in-game without having to modify the game itself.