Love this idea! As more authors come onto Nostr, it'll get easier to Zap whomever you read value (in Highlighter or wherever).
In normie world, I use ReadWise to collect highlights, resurface them periodically for memory, and also move them into RoamResearch for idea synthesis. Versions of those tools built on Nostr (like highlighter) would be amazing, and I'd be using them immediately.
I feel like we're getting there at such a fast pace, it won't be long!
