One Nostr service that I really miss is https://nips.be
I don't know what happened to the domain but it was sooo useful to get to Nips repo files quickly.
Discussion
I've read the owner of the domain has not renewed it.
I changed to https://nostr-nips.com/ to checkout the specs.
This one is also useful: https://nips.nostr.com
Mostly I just liked how short the domain was and how it indexed PRs as well as published NIPs