My team is looking at nostr to build a slack for devs, startups etc. We have already built a Discord alternative called Catalyze on Dfinity’s Internet Computer chain. Catalyze.one. Some have suggested we port that to Nostr as well. Lastly we built a Reddit for gamers and anime fans on the Sui chain. Gilder.io. Lots to do and happy to discuss what to go after first.