Now this one is interesting. This is your typical fan-made game using NES sprites and background graphics...that got Capcom’s official approval. In fact, it was made available on their Unity page. You can go there for more information and to download it. (It’s free, so, no concerns about royalties or anything, I suppose.) There’s another blog post detailing how you can get the soundtrack as well. Note: I don’t know if Capcom has a dedicated, permanent link for this game. As of this writing you can download it from the banner at the top of the Unity page; if this changes in the future, you may need to hunt around a bit for it.
Ordinarily I don’t review fan-made games, so I haven’t made up my mind yet if I’m going to officially cover this one, but it’s definitely going on the list.