Also, I should note that this effect works with all sorts of other media, not just Nintendo 3DS videos. I've watched a LP of super Mario Galaxy 2 using the method and I must say, it was pretty darn trippy!
Just remember, the 3D isn't always going to be evident... Something must always be in motion for it to work, and it has to be moving in a certain way.
Please WATCH THE ENTIRE VIDEO before commenting! Also, thumbs up if it worked for you and thumbs down if it didn't.