Hehe, I did the same thing 2 years ago [1], hooked up the mousewheel and also made it so the text could be selected and modified. Back then the browsers implementation was still very early and the text would disappear. Glad to see that it works properly now.
That's wierd - I show a cpu usage of about 48-52% on one of my four threads (2 cores) when I have the tab open, and under 5% on all with the tab closed.
This is on Firefox, Linux.
A side note: I started involuntarily humming the star wars theme to myself as the text started to scroll... I dare say: George Lucas has hacked my brain!
Intel i7 (4 cores w/ hyperthreading) running Ubuntu and Chrome 22 and that at one point was >60% on 3+ threads. On the bright side, it's great that Chrome is able to so seamlessly multithread complex CSS operations. That said, this is a rather fast CPU and I would have expected it to perform better.
It looks like most of the comments are about how the 3D scrolling text does not work in this or that browser. Detecting support for CSS3 3D transforms is nontrivial (and perhaps impossible).
[1] http://mrdoob.com/lab/css/starwars/