I haven’t yet seen EVERY site on the Web, but Bio-Bak is definitely one of the coolest sites I’ve seen in as long as I can remember. Upon entering the site, you navigate around simply by “dragging” the page around your screen. I recommend going with the full screen mode. You must find the toolbox, then the metal detector. Once you do that, the metal detector will help you find the missing tools. Once you’ve collected all the tools, you can “zoom out” on the site to see the much larger picture. And trust me, it’s worth seeing!
There’s a lot of animated illustration work on this site – quite frankly the whole thing is just stunning. Needless to say, if your client is looking for something out of this world for their Web site, this guy can probably help you out.