I was looking at one of those "what\'s different in these 2 pictures?" things one day. I noticed if I crossed my eyes i could bring the images together and the different areas showed up as blurry and mismatched. I circled the blurry images in about 5 seconds and got them all right.
Now, sometimes I will use this trick, (when no one is looking) for other things. I am a graphic designer and when I send a file to the printer and they send a proof back, sometimes I will do this to see if any text has shifted or any elements have been modified.
Has anyone else used this trick?