Wow, very appropriate, FF! I wasn't at all sure I could see these hidden pictures on my monitor--it is very difficult for me even when they're on paper; I can't even always see them. These things are just magical, to me--there's nothing there--but there IS!

For those who don't know, the trick to seeing these is to let your eyes unfocus a little, and keep them from re-focusing normally. I can get them unfocused by leaning forward till the surface picture blurs--my problem comes in preventing them from refocusing as I slowly lean back. And even when I can, it takes some time for me to be able to see the hidden shapes, but when I do...WOW!