I would have to search to find the Folding@Home thread about this which began in 2002. In 2004 the announcement was made that the programming was beginning. The status updates were limited by nondisclosure agreements with the GPU manufacturers, who helped supply information needed by the programmers. You could always ask the Scripps people at TSRI if they want to begin such a multi-year project. CPUs are a lot easier to program, and Intel and AMD are designing dual and quad core CPUs.

I suspect that most people will consider GPUs nonstarters until their development slows down and they start to look like a stable platform.

http://graphics.stanford.edu/%7Emhouston/public_talks/R520-mhouston.pdf