[sseagull]

I'm guessing the ncurses-based IM client based on libpurple (in other words, the text-based version of pidgin).

Which I used quite a bit when that kind of thing was more useful

[fuzzybear3965]

Ah, thank you! I did a quick search (just "finch") but nothing relevant was on the first page. "finch software" got me what I wanted (a few results down the page).