Just by checking https://lemmy.ml/communities one can see the most popular communities of lemmy.ml. The plan here is to list all the alternatives for those from other instances. One can also suggest alternatives to be added here and I update this living document.

• Anarchism --> !anarchism@lemmy.ca
• Anime --> !anime@jeremmy.ml
• Art --> !art@forum.dxcomplex.com, !photogrammetry@suppo.fi
• Ask Lemmy --> !askwomen@lemmy.ca
• Gaming --> !gaming@beehaw.org, !gaming@forum.dxcomplex.com
• General --> !general@forum.dxcomplex.com, !general@beehaw.org
• Green --> slrpnk.net, !environment@beehaw.org, !greenspace@beehaw.org
• Cryptocurrency --> !cryptocurrency@lemmy.ca
• Fediverse --> !fedizens@lemmy.ca, !thefedizenenquirer@lemmy.ca, !fediverse@midwest.social, !fediverselore@lemmy.ca, !bestofthefediverse@lemmy.ca
• Late Stage Capitalism, futurology etc. --> !aboringdystopia@mander.xyz
• Libre Culture --> !libre@fediverse.ro
• Linux --> !linux@sopuli.xyz
• Memes --> !memes@lemmy.ca, !memes@sopuli.xyz, !politicalcompassmemes@lemmy.perthchat.org
• Music --> !music@sopuli.xyz, !music@baraza.africa, !metal@lemmy.helvetet.eu, !music@beehaw.org, !midi@suppo.fi
• Open Source --> !opensource@lemmy.helvetet.eu
• Piracy --> !piracy@poggerinos.ml
• Politics --> !moderatepolitics@sopuli.xyz, !politics@beehaw.org, !politics@gtio.io, !geopol@sopuli.xyz, !politics@lemmy.helvetet.eu
• Political Humor --> !politicalmemes@lemmy.ca
• Privacy --> !privacy@lemmy.ca, !privacy@community.nicfab.it, !privacy@nrsk.no, !privacy@sopuli.xyz, !privacyguides@lemmy.one
• Programming language communities --> !programming@beehaw.org
• Self-Hosting --> !selfhosting@slrpnk.net, !main@selfhosting.pub
• Socialism --> !socialism@midwest.social, !armchairsocialist@lemmy.ca
• Science --> !science@beehaw.org, !science@mander.xyz, !science@gtio.io !music@forum.dxcomplex.com
• Technology --> !technology@beehaw.org, !technology@gtio.io, !tech@links.roobre.es, !technology@forum.dxcomplex.com
• Videos --> !videos@nrsk.no, !video@baraza.africa, !videos@sopuli.xyz
• World News --> !news@beehaw.org
• Misc --> !sauna@suppo.fi