I've been playing around with the Publicis & Hal Riney website. They have provided the option of navigating the website through gestures picked up by your webcam. I've seen this idea demoed before, but I've never just come across it on a website. I have to admit, the first time I tried this, it wasn't working for me at all. My interpretation of the gestures was a bit too exaggerated (or their interpretation wasn't exaggerated enough). Once I figured it out, I was really enjoying the interaction experience. The novelty of the physical action (beyond my finger on the mouse) kind of snapped me out of my normal internet browsing glaze and made me pay much more attention to the content. It also kept my interest and made me explore much more of the site then I might have otherwise.