Distributed computing is a neat idea, I think. Not sure if it's been covered in the Cellar yet, but what do you think the implications of it are?
The fine folks at Stanford U. are trying to understand protein folding and how a misfolded protein can result in things like Alzheimer's disease, Parkinson's, etc. The science is beyond me, but apparently, simulating the protein-folding process is quite a resource hog. So, a prof at Stanford has implemented
Folding@Home, wherein you can donate your unused CPU cycles to their timescale simulation, maybe even helping cure a disease in the process.
How cool is that? It's like the photo-negative of a pyramid scheme.