A recent Microsoft patent details how the cumbersome proof-of-work implementation on current cryptocurrencies like Bitocoin that has ever-increasing processing power requirements can be replaced with a system that validates user body activity. This would allow more users to adopt blockchain tech and possibly revolutionize finances.
https://www.notebookcheck.net/Microsoft-could-revolutionize-cryptomining-with-user-body-activity-proof-of-work.459192.0.html