HAHA! Funny enough, two weeks ago I wanted to learn how to create unique NFTs and a friend said "if you can sell my soul with an NFT, I'm in" ... yesterday I pushed the first test live (no minting yet) https://test.soulz.art
Interesting idea. Perhaps ownership of a soul NFT could be used to bypass captchas or otherwise prove that actions were undertaken with authority of a human. If a soul was abused by authorizing too many requests then it could be sent to "hell", where it's blacklisted globally.