A new and exciting use of blockchain is on the horizon. They call it Golem. The Beta version, or Brass Golem, is focused on proof of concept with rendering in Blender, and LuxRender, complete 3D art programs. Eventually updates to Clay, Stone, and then Iron will add more functionality, with the idea being you the "provider" can rent out your unused CPU, GPU, and HDD to "requestors", and vice versa, in exchange for Golem Tokens to use on the network or trade for other coins/USD.
The goal is to create a global supercomputer, with almost absolute perfect market metrics, for utilizing unused computing power. You download and setup the golem program, the developers then take the scenes they have created where they parcel them out, in pieces you can compute for reward.
Here is the link for setup, https://github.com/golemfactory/golem/wiki/Installation. The program is only in its beta stage, so it is only being run on a test network at the moment, but you can go ahead and get started before the full network goes live!