Hopefully this has provided enough information for the casual electronics hobbyist to create a set of USB NES controllers without spending a ton of money (and maybe learning a thing or two along the way). If you enjoyed this article, I encourage you to donate to help fund future projects like this one.
I will leave the reader with an idea; I have also created a set of wireless USB remotes by simply including a transmitter in the controller. The main problem with this is that the controller needs batteries because it can no longer be powered from the USB port. It is a non-trivial task to fit batteries in the controller because lets face it; there just isn't that much empty space in there. This also requires two microcontrollers instead of just one, although the one inside the controller can be a very simple one now (12F or 16F series PIC).