Jabber a bit,
AOL Messenger,
Blackberry messenger,
Bloomberg Messenger (bank paid 2k per month for it!),
Skype for messaging,
Keybase (kind of cool but too heavy),
Slack,
and now Element Matrix.
Its one place sometimes I think regulation might be good to force standardization (like electricity or phone standards).
Oh and when I go to asia I use the ones there - viber, line, wechat etc.
Nice https://memegenerator.net/img/instances/24953235/nice.jpg
It's amazing how much spinning happens in current media. The only people in the world who truly know how much this is are those who get the headlines before the stories are written and talked about, like day traders, who get it for speed reasons. It's cool, but it sucks it costs so much to get an unfiltered news source.
IRC
ICQ
AIM
Trillian
Skype
Slack (just co-workers)
Discord (just co-workers that are friends now)
Must be like over a 30 year period of time.