SIGGRAPH, the worldwide reference for graphics-related topics, proposes videos from most or even all of the topics on the conference on their website, in a section called SIGGRAPH Encore. Encore features videos with topics ranging from bare-metal programming courses like the Basics of DirectX 10 programming (6 hours non-stop straight, ouch!) to others that explain more artistic techniques like “From DNA to 3D Organic Art Forms”.
If you were interested, but didn’t have a chance to go, like me, Encore gives you free access to the 1100 videos from the last 3 years, ending on october 31st, 2007. You can look at the videos, but to download them on your local pc, you are still charged for it. They call it ‘Watch for free, Download for a Fee’.
For the last few years, Blender has been present at Siggraph, I might even watch some things about it if I can find them in time.
The videos are in Quicktime format, and I didn’t test them in Linux yet, so your mileage might vary.