IRC
Iโve always liked the idea of IRC, but donโt often use it. Iโm more likely to lurk in channels; it feels weird talking with random people online, but I think this has more to do with social anxiety over a problem with the technology. IRC itself feels like one of the few open standards still readily accessible, actively discouraging walled gardens like Discord.
I often lurk on:
I run a test version of the Ergo.Chat software to fool around with, but itโs not externally accessible.
For IRC clients, Iโve used WeeChat with a ZNC IRC bouncer to stay logged in. Iโve also recently started fooling around with The Lounge as a web-based IRC client.