Would it be possible to create a cryptocurrency that uses it's collective mining hashpower all at once, creating a massive supercomputer to solve complex equations, or a string of equations provided by the highest bidder?

I see this as a cross between NiceHash in that it pays other people to rent out other people's computing power to the highest bidder, Folding at Home in that it's solving complex equations (but not limited to must folding proteins), and a Super Computer.

Could the NiceHash server be decentralized? Can this be done today in Ethereum or other Alt Coins?