I just had to share this!
While viewing this collage http://collagemuseum.com/Bakers/Bakers5/exb13.htm I scrolled down the page using the mouse wheel.
The image got smaller and smaller as if I was shrinking it by percentages. I thought that was weird because I wasn't viewing this as a magnified image; it's just a page. Then I used the scroll bar on the side to go up and down and got a different experience.
I tried it with some other collages on the site and didn't get the same shrinking effect.
I wonder if the collage artist knows about the cool, illusionary effect!