> you can get a strong cryptographic identity for (almost) anyone on the service, which you can then sign/encrypt to, verify for, etc.

I made https://sshign.tcardenas.me/ to take advantage of this. For example: [1]

In the end, it isn't that useful. I only routinely sign digitally to deal with the (Spanish) government, and they provide their own certificates and software to do that.

[1] https://sshign.tcardenas.me/?signer=github.com%2Ftcard&messa...