Not counting the smartass answers like some of the others (which are all 100% correct lol): The Fediverse platforms I use are:
kbin
Mastoson
BookWyrm
pixelfed
Peertube
The former 2 I use primarily, the latter 3 just on occasion. I do also have a couple of Lemmy accounts on other instances but no longer use them.
Fuck lmao, leaving it.