Kokichi Sugihara, a mathematician at Japan’s Meiji University, is something of an expert on creating 3D versions of the kinds of impossible objects popularized by MC Escher.
And 'impossible' is exactly what we thought while watching his latest illusion, a gravity-defying house, in action:
What’s basically going on here is a variant of the ‘crater illusion’ – that sensation you sometimes have looking at pictures of the moon’s surface when you can’t tell if you’re looking at a crater or a mound. The brain attempts to use the orientation of shadows to tell the difference between convex and concave, but it’s a system that’s easily fooled, as Sugihara shows here. The contrast between our first assumption, and the inappropriate behavior of the marbles, gives this illusion its kick.
For more of Sugihara's work, check out this impossibly cool slope illusion.