Similar in purpose to this one: finding the right community for you (but with no commentary on how active they are)
https://lemmy.ml/c/findacommunity
https://lemmy.ml/c/[email protected]
https://lemmy.ml/c/[email protected]
https://lemmy.ml/c/communities
https://lemmy.ml/c/[email protected]
https://lemmy.world/c/newcommunities
ANNOUNCEMENTS and PROMOTED DISCOVERY:
https://feddit.de/c/ankuendigungen (Announcements - German)
Doh! (I created that last night too) - added thx