Mostly unconsciously we have a clamor of sensory information assaulting our minds continually (unless maybe when we are asleep, and I'm not sure about then).

Cognitive scientists such as Daniel Dennett and great magicians like The Amazing Randi got together to discuss "Sleights of Mind."

Take a lòók at the link below. There are two picture there that look identical but have 3 subtle differences. Thousands of people have been tested with only a handful finding all three. I was only able to find 1 myself.

Unfortunately the directions are in German but all they say is "find the 3 differences".

The pictures are here.

Here are two versions of an illsions that are rather funny, but the reaction of the crowd (at least in the first one) is what will get you laughing. When I found this first illusion on YouTube I assumed that maybe a fake head was used.




However after viewing the same, or at least a similar illsion below on stage, it is apparent that the head isn't fake. Props of some kind are being used instead.



Anyone care to speculate in the comments on how this is done? I think the performer must be ducking down (while looking forward) with props to keep the cape or jacket rigid.