AT LAST someone pulls this off! I love primecoin for it's intrinsic utility on top of making some coins, but this is outstanding!
Now, what safeguards do you have to validate the folding work? What simple proof-of-work is there? What prevents someone from submitting garbage?
Great questions! Since the folding isn't actually integrated into the blockchain but is rather an independent reward system (therefore the network keeps its cryptographic security, and protein folding doesn't bloat the blockchain), the work validation is done by the work-providing network. To start off, we are only using Folding@Home, but as the project grows, the beauty of the separate GPU/CPU computation pool is that more can be created to allow work done for other awesome projects as well. The F@H project handles stopping submitted garbage, and has some downright awesome protection against exploits. Work provided by work servers is provided redundantly, so if one person submits junk it's easy to pick out the incorrect workunits, and points will, for them, not be rewarded.