NES controller on an Atari 400? has it been done?

So ive recently picked up at Atari 400 computer, all stock. I will max out the ram, add composite video in the future, but for now I want to do something with the joystick. Ive seen modded nes controllers (using stock atari joystick cords) that worked on nintendos. So I assume that I can do the same mod, or a similar one, so that i can use a nintendo controller to play games with.

Does anyone know if this would work, or have seen it done? I know some people love the old joysticks, but to me they were always a pain.