I’ve only used a few so far. Mastodon, Kbin, and Lemmy. Lemmy is my daily driver; I’m not really a microblogging person.
I’m interested in Friendica, Piefed, and Pixelfed too. BookWyrm’s concept is cool as shit, I just don’t read enough books to make use of it (this needs to change). There is an idea I heard about a community driven recipe/cooking fediverse site, that I heard on a podcast (decentered podcast I think?) that sounded really cool and like something I’d probably use often.