A bigger issue than lying (and randomly failing) clients is the fact that you're farming out your users data to third parties. You might be willing to trust a s

A bigger issue than lying (and randomly failing) clients is the fact that you're farming out your users data to third parties. You might be willing to trust a single entity like Amazon, Microsoft, or Google, who have a reputation to maintain / can be sued (for potentially a lot); but if your farming out to essentially anonymous individuals, there's no repercussions for, say, using their credit card information. Now, there are definitely use cases where you don't care; which would be a cool application for this; but unless we figure out how to do homomorphic computing, this doesn't seem immediately likely to impact cloud computing prices; even if it was cheaper to simply use excess compute capacity (which I'm not convinced it is).