Pretty cool

[RErender]

http://www.johnsadowski.com/big_spanish_castle.html

[Dman3d]

bandwidth exceeded

[Paul Oblomov]

Nice illusion. :P

[RErender]

What's really interesting is that it will persist as long as you don't move your eyes or focus.

[tom182]

I love those things, they never fail to amuse me,
have you seen the spinning spiral one, i.e. the one that messes with you eyes/perception so much you'd swear you had down'd acid tab, albeit for about 5 seconds.