Stacksmashing got Doom running on Nintendo's new Super Mario Game & Watch [Amazon]. The classic shooter had to be pared to the bone to run on the retro handheld and is barely playable: it's probably not a hack worth doing yourself. But it shows two interesting things. First, it shows how efficiently-crafted the Game & Watch is, with a bare minimum of computing power required to run a classic game. Secondly, it shows how powerful that absolute bare minimum now is. Soon it will be hard to source a system-on-a-chip that can't run Doom. Eventually it will be hard to source a display whose controller chip can't run Doom.