I’ve been having a fun time at home with a DIY squaring the circle project. (Okay, for the 3-D purists, you’re actually turning a cylindrical tube into a rectangular tube.) There are no camera tricks in the image you see above. What you see in the mirror is the actual reflection of the object in the foreground on my desk.
It’s called the Ambiguous Cylinder Illusion, and I’ve actually referenced it on this blog once before, but the fun thing is that you can create your own paper model as I did, by going here and downloading the printable pattern. Just scissors and tape completes it. It’s very easy, and you too will be able to square the circle.