Knowledge

A bit of knowledge on optical illusions. Or scroll down to see what you came for.

Can animals see optical illusions? Hosico cat shows it with optical illusion rug

Disappearing trailer

Source/credit: powerbookguy

This disappearing trailer is so confusing. OP said it was just as confusing in real life as it is in the image. Until you see it from a different angle and know that the structure on top of the trailer is shaped like a triangle, and you are looking at the right side panel head on.