nostr-filter is a very interesting "relay", it is not really a relay it's more a filter relay that you run before your relay. it can be used to filter events, user, ip addresses, content... the best part of it, it can be run before any relay and it sends then only the filtered events to your own relay.
i see more and more questions about nostr relays, would it not great to have a nostr community for this? so we have verything in one place? what do think @rabble and @jascha ?