What kind of Mastodon discovery tools are available? Off the top of my head, things that would be nice:

"Who are these people?" - Show me a few posts (not boosts) from each of my most recent followers.

"Actual social network" - Show me posts from the people followed by people I follow, and who the link is. LJ called this "friendsfriends" and it was cool.

"Trending" - posts boosted by people 2 or 3 hops away from me, ordered by number of boosts, and omitting ones I've seen.