From Stanford:

Introduction 

Since 2000, Folding@Home (FAH) has lead to a major jump in the capabilities of molecular simulation. By joining together hundreds of thousands of PCs throughout the world, calculations which were previously considered impossible have now become routine. FAH has targeted the study of protein folding and protein folding disease, and numerous scientific advances have come from the project.

Now in 2006, we are looking forward to another major advance in capabilities. This advance utilizes the new, high performance Graphics Processing Units (GPUs) from ATI to achieve performance previously only possible on supercomputers. With this new technology (as well as the new Cell processor in Sony’s PlayStation 3), we will soon be able to attain performance on the 100 gigaflop scale per computer. With this new software and hardware, we will be able to push Folding@Home a major step forward.

Our goal is to apply this new technology to dramatically advance the capabilities of Folding@Home, applying our simulations to further study of protein folding and related diseases, including Alzheimer’s Disease, Huntington's Disease, and certain forms of cancer. With these computational advances, coupled with new simulation methodologies to harness the new techniques, we will be able to address questions previously considered impossible to tackle computationally, and make even greater impacts on our knowledge of folding and folding related diseases.

Continue reading about this here.

If you have questions about folding using an ATI GPU, please ask in the forum.