It is quite possible that one decides to design a device that can take input from a (wired) game controller like the NES, SNES, PS1, PS2 controllers which are going to have their own protocol. For a PS2 dual shock controller, designing something that can decode the protocol is a project in itself.
However, always there is a problem of where to get a connector for the "consolve side" of the controller connection. When the game console was manufactuered, they put in a connector on the front. However, if I want my own design project to take input from e.g a PS2 dual shock controller, how do I get the "female" connetor that shall go onto the PCB? Any ideas?
One possibility is to design a connector and print it using a 3D printer, that however is a project in itself and it still needs to be considered how the metal contacts will be put in.