A Mastodon client-bot which, when ear-burned in a post, puts the post into a database which can be browsed by category.
So, basically opt-in indexing of posts, with a UI which provides functionality equivalent to Circles on G+ except done right.
Categories could be assigned by hashtag, and the bot's curator could combine certain hashtags that refer to the same thing.
Each category could have its own RSS feed or, heck, a bot which reshares the posts (not that Masto is the best UI for topic-feeds).
I could write this. o.0
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