> AFAIK there aren't really any good solutions to prevent this problem- For complex game-theoretic reasons, simply changing the mining algorithm to something di

> AFAIK there aren't really any good solutions to prevent this problem- For complex game-theoretic reasons, simply changing the mining algorithm to something different doesn't really offer much protection. (Some folks believe if these smaller currencies were to move to "proof of stake" it could help solve this problem, but this is an extremely contentious topic.) Decred's mixed PoW/PoS would be extremely expensive to 51% attack, and would require a large amount of funds to be locked up in voting tickets for random amounts of time ranging from a few days to several months - so if you successfully attacked it, you'd presumably reduce the value of Decred and the many millions of dollars worth of Decred you had frozen in tickets.