Unless I missed something[0], the work is actually useful in cryptocurrencies: it's actually bruteforcing a crypto function to find a solution for the block. On

Unless I missed something[0], the work is actually useful in cryptocurrencies: it's actually bruteforcing a crypto function to find a solution for the block. Once the solution is found, the block, which contains actual transactions, is known to be valid, and the block is said to be mined. The very system that generates money is the system that validates the transactions. The miner gets the nominal fee of 25 BTC per block, plus any fees included in the transactions. [0]: http://www.righto.com/2014/02/bitcoins-hard-way-using-raw-bitcoin.html http://www.righto.com/2014/02/bitcoins-hard-way-using-raw-bi...