Here are some illusions that will make your head spin. All of these are JPG images, they are not flash or any video. On most of these if you stare at different spots, you will notice that the movement stops. If you put your mouse on one spot that seems to move, you will be able to see that it is not moving at all. 
The center circle seems to hover around.
If you stare at the center dot,
then move your face closer and further away from the screen,
the circles move.
The center circle seems to hover around.
If you stare at the center dot,
then move your face closer and further away from the screen,
the circles move.