But now Marco Kuiper from marcofolio.net adds another usage for it. He created a cool optical illusion with just plain css/html and some pictures. You can see a demo of this effect in action on Marco’s website. Head over to the demo and resize your browser window. You should articulate something like “whoooot!” now. Marco has written some words about it too and you can download the demo. He has also done a nice tutorial how to achieve this optical illusion. Very cool!