There is also a proposal for NIP-97 by @semisol which uses NIP-98 
I added support for this in Nostur but there are no websites or services that support his yet.
GitHub
NIP-97 Login with Nostr by Semisol · Pull Request #1042 · nostr-protocol/nips
This spec proposes a simple login flow to allow easy authentication to services like nostr.build without having to deal with DM verification or oth...
If your website requires login, consider adding login with nostr.
Demo: 
NIP-97: Login with Nostr: https://github.com/nostr-protocol/nips/blob/login/97.md
View quoted note →
NIP-97: Login with Nostr: https://github.com/nostr-protocol/nips/blob/login/97.md