Pi Zero just came back in stock:
https://thepihut.com/products/raspberry-pi-zero
Not as powerful as the Pi 3 but still capable of running retropi. I wedged one into a Xbox controller but I've seen people put it in a NES controller.
https://thepihut.com/products/raspberry-pi-zero
Not as powerful as the Pi 3 but still capable of running retropi. I wedged one into a Xbox controller but I've seen people put it in a NES controller.