The lights are on
So, I'm seeing all of these threads for SNES and N64 games, and yet none for the original: the NES. So...what's your favorite NES game? Obscure or mainstream, it really doesn't matter. That game that you just played for hours and (quite possibly) even still go back to play.
Personally, I was always a huge fan of Megaman 5 and the original Legend of Zelda.