Nice! I had written a little algorithm that one could use to implement something like this (maybe interesting if you want to understand how it could work): http

Nice! I had written a little algorithm that one could use to implement something like this (maybe interesting if you want to understand how it could work): https://github.com/fabiospampinato/crypto-puzzle https://github.com/fabiospampinato/crypto-puzzle I think there's something to this, it costs you next to nothing to generate these puzzles and you get a guaranteed, tunable, slowdown factor on attackers (or cost increase for them I guess).