That's really ingenious, but I'm docking one star because I'm pretty sure user input was needed to go down that pipe.

I was going to give it a 4, since there is some user input required, until I saw the boss fight.

Also, you pretty much have to hit a button to grab the shells. Still, pretty damned impressive. LOOK OUT!

Even if it did cheat a little, that's just clever as hell.

http://www.joystiq.com/2007/08/22/dont-move-hacked-mario-world-lev els-play-themselves/

There's about 10 of these in total here (which is where I found it). This one is far from the best one after having sat through them all so check them out.