I love the idea of inserting crypto into the Geocaching world! I did a quick search and nothing of interest came up in the top results for either "crypto" or "bitcoin". I'm not sure how you would fund it but there are several kinds of geocaches that pose some sort of challenge where the people who complete the challenge could receive a wallet with just a little crypto so they would also face the challenge of accessing the wallet also. We go by MLdiehlcitoli on geocaching.com. Thanks for the post!