Click on the image to zoom in. What can you see?
The annual Illusion Of The Year Contest winners are featured on NewScientist.com. They give a god insight into how our brain processes visual stimuli and look really cool at the same time. Here is the winner:
One of my favourites is this flash animation of waveforms with toggles to control what you focus on. Try it!
All of the illusions (from 2010 and before) are online here: