If you like the neat color optical illusion posted by Neatoramanaut Minnesotastan from the Upcoming Queue, check this one out by Rob Jenkins of the University of Glasgow and Richard Wiseman of the University of Hertfordshire:
The picture below shows two monkeys. Set your computer monitor to maximum brightness and then stare at the centre of the picture for about 30 seconds without moving your eyes. Next, look to a white wall and blink a few times. The monkeys should suddenly transform into a perfect picture of Darwin!
Previously on Neatorama: 10 Fun Facts About Charles Darwin