So, for all you new users, there's this OStatus thing called "groups", which is indicated with a bang ( ! ), where you can follow, say, a topic (music, security, crypto, games and whatnot), or a specific thing (emacs, coffee etc.), or even a greeting (the tzag group for Time Zone Appropriate Greetings), regardless of who posts about it.
It's a pretty powerful tool, all things considered, and !fediverse and !fedgroups may be of interest for exploring what's out there.
Also, for all you infosec peeps there's of course the !security group, there's also one for !musicians, for !ccmusic, for your current !listening habits, etc.
A limitation is that groups live on a specific instance, though I think there might be proposals to mitigate that...