Some exciting projects already launched, and the promise of more to come. These are in the plus column for blockchain - and could make big differences.

But on the negative column must surely be how power-hungry mining coins is. Mining centres use massive amounts of energy to sustain the blockchain revolution at the moment.

It might be a good idea to introduce some sort of incentive for miners to use cleaner energy, such as solar power. Maybe their rewards could be linked to a ratio of clean/dirty energy used in their mining project. This obviously isn't possible (at least for now) for all miners, but it would be for large mining centres.