Assuming you are the retro love that can’t seems to have enough with your old school NES console, you might want to check out this cool mod by the fans. It’s an Arcade controller that take and turn the whole NES console into the arcade controller.
You won’t be able to slide in any game cartridge inside the tray because it’s a non-working console. This Retro NES arcade controller has provided controller stick and 8 arcade buttons, however, I don’t have anymore information regarding this controller. I assume it would be a controller for PC/Xbox/PS3.