People still use our old-fashioned Unix login servers

We have these at work and there was a big outcry when IT tried to get rid of them. I use them from time to time to do things like: Keep git and other backups. Convenient place to scp files to/from. Upload files that coworkers can grab. I don't use it, but others used them as permanent IRC endpoints (using screen or tmux presumably).

Notice a cloud VM or container probably doesn't work here. You need something with a permanent presence, and shared between users (with separate Unix accounts).

Using IRC for the company IM is true old-school. I've worked at places which do the same, and also use SIP for A/V calls. Not being dependent on Big Tech, or the Internet for that matter, for services which exist entirely inside the corporate LAN is a great way to work.

It was replaced by Slack last year. Sigh ...

We still use IRC in some upstream communities although it has been replaced by Matrix in some (which is also terrible).