Discord is a VoIP, instant messaging and digital distribution platform designed for creating communities. Users communicate with voice calls, video calls, text messaging, media and files in private chats or as part of communities called "servers".
Too oldskool for the new stuff? We got you covered with a channel on IRC:
LiveJournal (Russian: Живой Журнал), stylised as LiVEJOURNAL, is a Russian-owned social networking service where users can keep a blog, journal, or diary.
Reddit (/ˈrɛdɪt/, stylized in all lowercase) is a social news aggregation, web content rating, and discussion website, recently including livestream content through Reddit Public Access Network.
These Yahoo groups used to be active back in the days, long before the current social media channels.
Sadly Yahoo removed all groups.