http://www.newgrounds.com/portal/view/484770
I haven't played it for more than a couple of minutes but the basic premise is... the duck hunt dawg has blown up your crib and kidnapped your girlfriend. Mario, Luigi, and Mr. T band together to kill to take down those nasty koopas with zappers, shotguns and wii motes.
Interesting.
I like how the first screen has an impassable barrier, unless you know the trick of it. Terribly impressive, and totally designed to annoy the hell out of any new players.
Oh, and the shift key does nothing. I wonder if that's related.