The Hivelogic Narrative is a well-respected weblog. Very bizarrely, it is written in the second person. Today, it links to this set of optical illusions. They play off how odd it is that our brain is able to construct a three dimensional world out of the two dimensional images it gets.
There are a bunch of rules that filmakers have to follow when they’re making a movie for the audience to be able to understand what they’re seeing. If done wrong, viewers will get confused when, for example, an actor walks to a door that they thought was on the other side of the room. Citizen Kane is famous because it played with these tricks. In one scene, Kane appears to be standing in front of normal windows which are actually absurdly large and start at head-height. This works because your brain is fooling itself into believing that the images on the screen represent the real world.
Anthropologists curious about this once set up a movie screen in front of a tribe that had never seen movies or photos before. The people had no idea what they were looking at, seeing just a large, bright screen. They watched curiously for minutes, unable at all to see the movie, until a chicken appeared. Once they had seen the chicken (which they recognized from daily life), their brains were able to identify the images and could then understand to turn the flat signals into an interpretable concept.
Update: Tripod doesn’t want me linking to their images directly. To see the Citizen Kane pictures, go 3/4 down this page.