But you have to run it 24x7 and be connected to the network. Not going to work for those in Africa, they will be suffering the effects of inflation, while people who can afford a EC2 micro box won't.
My understanding is that Proof of Stake is based on coin age - so if you keep unconnected for some time you can still capitalize on that when you connect back - because your coin gets older and thus has more power in the Proof of Stake lottery.