It's so obvious, after you figure it out. :lol:

took me a few flicks before i figured it out.

here are some more from the same place, but a little different. requires shockwave for them to work.

http://nivea.psycho.univ-paris5.fr/S...bis/intro.html

Merry-go-round (noticed after one viewing)
Snake (had to restart it about 10 times before i figured it out)
Bistro (took a couple of restarts)
Lab Frogs (after one viewing)
Yack (took alot of times)
Workroom (took a couple of times)