it never occurred to an 8 year old me how game genie worked and 25 years later, I had sort of forgotten about it.
It, like the Virtual Boy and the camera/printer peripheral were a few game boy accessories that were totally ahead of their time.
I pull them out every once in a while. The Codebreaker is more interesting to play with now than it was as a kid actually, because I can understand more of its functions.