Luxo Jr, at Upcoming Pixar, just posted a link to some of Pixar’s animation secrets. It’s a storage area for technical papers some a few years old, some just presented at SIGGRAPH 2006.
The page is full of technical memo’s from Pixar such as, Interactive Depth of Field, Harmonic Coordinates and Statistical Acceleration for Animated Global Illumination. The memo’s include videos to help illustrate what is going on.
Right now it’s available unpassword protected at http://graphics.pixar.com but don’t count on that for long.