How To: Create an optical illusion with any color photo

This will show you how to take negative afterimages to another level. By introducing a negative color photo and then immediately incorporating a black and white version of the same photo, you will perceive the black and white photo in full color (the way the color photo was meant to look). This can be done with any color photo, along with any photo editing program, like Adobe Photoshop.

Get the full instructions at Greeenpro's Instructable's article.