Watch your very world around you distort!
Seeing is believing..... or so they say. Well believe it no more, because as these animations will show, your very world is going to distort around you! After clicking on your prefered choice, sit up fairly close to the monitor screen and stare into the center of the animation for a minute or 2. Once you've done this, look at something else, and your vision will go haywire! Things will really look as though they're shrinking or growing!
The illusions will work through your browser just by clicking on them, but I recommend trying them through an external player such as the excellent multi-purpose Irfanview (which can be download from the homepage), or in particular, the specialist animation player - Moyager (which can run GIF animations at a smooth speed of 50 frames per second). Running the animations through either of these players will enhance the illusion to a large degree.