But ATI's solution is free (Score 2, Informative)

Admittedly it's not exactly the same things as NVIDIA's solution, but the main component of breaking big movie quality shaders into multiple passes is in ATI's Ashli (http://www.ati.com/developer/ashli.html). The big plus is instead of costing thousands of dollars it's free. Also I noticed everyone is saying agp read backs make this sort of thing useless. The fact is that most of the scenes rendered will take seconds to hours on the graphics card (vs. minutes to days on a CPU). The slow agp reads aren't going to be much of a performance impact in these situations.