I love a good optical illusion and there's a 15 second video from a user named Boom Fire making the rounds that is absolutely spot on. At first it looks like a typical wooden chair, but when the young man goes to sit on it he ends up perched on the arm. When the cameraman changes perspectives you can really see what's going on.

I followed the next video in the queue and found the explanation for this chair and even more mind-blowing examples of optical illusions from Zach King.

Thanks for the explanations, Zach. I really wouldn't mind having a few of these in my house.