With Rana cli you can do proof of work on hour npub🤙

If you generate enough random npubs, you'll find one that starts with an actual word. nostr:npub1sn0wdenkukak0d9dfczzeacvhkrgz92ak56egt7vdgzn8pv2wfqqhrjdv9 has one too if you look. Lots of people made vanity Bitcoin addresses the same way.

Took me a week to mine my npub on my MacBook. Totally worth it.