XrayMan
Boogyman93
vlad01
XrayMan
Shake your head from left to right, right to left, and repeat simultaneously until you see him. Cool trick! 
or you can just blur your eyes. Thats easier!
Or you can just take 2 steps away from the screen and the image becomes visible. That's even easier!
But I don't know who it is. To me it looks like either Rick Astley or Neil Patrick Harris. But I bet it's neither of them.
It's Neal!
Don't have to stand back, don't have to shake your head. Just unfocus your eyes. The picture is made up from shades of grey hidden in the white bars. Basically its similar to anti aliasing effects on video cards.