The Snowman: A Stereogram Animation 

[This video is best viewed in the small player window, not full screen]
There is no need to adjust your monitor... just your focus. :)
For those of you who can see stereograms, I hope you enjoy this!
Never seen a stereogram before? The goal is to unfocus your eyes and look through the screen, until the repeating pattern merges and you see the 3D image.
Three tips that might help to look through the screen:
1) Try focusing on the wall behind and above your computer screen, then keep your eyes focused at that distance but move them down so that you are looking through the screen.
2) If you have a CRT monitor, try focusing on the reflections in the screen.
3) Start up close to the screen, unfocus your eyes so you're looking through the screen, and slowly back away.