[GordonS]

But why would a blockchain be any better than a peer-to-peer filesystem, for example?

Also, it seems like a really bad idea to have your encrypted passwords open for anyone to have a crack at - any flaws in the b.lock encryption protocol or implementation could have disastrous consequences. Unfortunately I wasted some minutes of my life looking into their encryption, and it's bad (not using authenticated encryption, using a malleable encryption mode (CTR), directly encrypting secrets with your wallet private key...)