The biggest, obvious one to me is news. Say what you will about mainstream media but some great investigative journalism still happens, and these companies are in an awkward position where no one wants to pay and everyone uses adblockers.
When I'm not living paycheck to paycheck I want to support Standard Ebooks (they're doing a great job of showing how to make ebooks that don't suck, check out their style guide) and maybe Neocities.
The more I think about how Medium works, the more I think it makes sense? While they could have done the typical thing where the people hosting content there pay for their share of the servers, by doing it in reverse the individual monthly cost can be lower (casting a wider net) and the people writing for them can actually get paid a bit for doing so.
I'm thinking about throwing some money at Obsidian, too, since I practically live in that app.
...Oh and obviously Fedora considering I rely on it to use my computer at all.
^On an unrelated note, how am I the first person to leave a comment?^