Look deeper... deeper!

Optical illusions reminiscent of the LSD-fueled art of the 1960s (or, for that matter, of the X-inspired art of the 1990s) are a bit passe, but this optical illusion video does a trick I hadn't seen before that is pretty cool, so I wanted to share. Plus, putting this up allows me to post something other than music -- variety is good, right?
It takes a while for the effect to work, so it might get boring, but if you make it to the end you just might find it was worth it. The mind and the eyes are fascinating pieces of biology, aren't they?

Here's the link.