> what do they do? Can you point to some successful use-cases today (other than some kittens) where this might apply? Nitpicking but ain't collectible card gam

> what do they do? Can you point to some successful use-cases today (other than some kittens) where this might apply? Nitpicking but ain't collectible card games with proof-of-ownership a use case though? In the Magic The Gathering world (for real physical cards) ensuring that thought-after cards are the real thing is an issue. There are brick and mortars grading companies grading the cards. Then you have to trust the seller you're not getting a swapped-in chinese fake. But another use case I've seen used: fully decentralized messaging, either "pseudonymous" (say tied to a BTC address: there's been a working demo showing on to do this on BTC's lightning network) or fully anonymous messages, using ZK cryptography. In this case you don't know who send a message to whom. You don't even know if it's a message or an amount transferred. And if the cryptographic primitives behind that are broken, we would pretty soon know (price would crash). To me decentralized messaging, fully anonymous using zero-knowledge cryptography primitives, is quite a use case compared to the "we-need-your-phone-number-but-trust-us-our-protocol-and-app-ain't-backdoored-and-we're-not-collecting-any-data" messaging solutions that are out at the moment. But I agree it's a world obviously full of scam. Still: a blockchain is basically a computer: a very slow and bloated one. But it's also an incredibly correct and very hard to hack computer. I think there are valid use cases for a fully decentralized computer running advanced cryptographic primitives like zero-knowledge cryptography. To me fully anonymous decentralized messaging is one (and a badly needed one at that). There are probably others.