Eyes working OK?

[catso]

Then try this





More at;

www.ritsumei.ac.jp/~akitaoka/saishin2e.html

[rob_f]

Some twat has put that poster up in our lounge at uni, really bloody irritating it is.

Rob.

[shadowninja]

argh!

[pstruck]

Whoa! I feel ill now.

[LongQ]

This one will probably puzzle you but is unlikely to make you dizzy.

http://web.mit.edu/persci/people/adelson/checkershadow_illusion.html

[Pigeon]

Been to Keswick lately?

www.puzzlingplace.co.uk/