Very cool! Fun fact, this is basically a simplified version of bitcoin mining.

In order to mine a reward of 3 bitcoin, you just need to find a sha-256 hash that is lower than 2.7×10⁶⁷

https://bitcoin.stackexchange.com/questions/85896/mining-difficulty-and-leading-zeros

The world currently calculates around 780 bitcoin exahashes/s, so one of these $300k hashes is found about every 10 minutes on average.

https://www.blockchain.com/explorer/charts/hash-rate https://www.coinwarz.com/mining/bitcoin/difficulty-chart https://www.bitcoinblockhalf.com/