> That would be exactly my own reaction if it would ever happen to me. But so far, unfortunately, it was always either Hipchat or Skype.

Both the IBM LTC and Intel OTC maintain internal IRC servers. They aren't used by the entire company, but they're used by those Open Source groups. (Company-wide IM is still Sametime and Lync, respectively, but both of those are usable from Linux with Pidgin.)

I had a 2-week temporary gig at another place (was going perm, but I got a much better offer from the current gig at the last minute).

They used Hipchat, and it was neat - my coworkers there greeted me with inline memes. Having to use a proprietary client sucked, though.

Actually just went through this exact situation last week. Temporary gig seeing if I made a good fit, didn't like the contract they wanted me to sign.

I just set up bitlbee to do XMPP in irssi. Hipchat is accessible via XMPP. Lots of little annoying quirks but it was better than nothing.

Hipchat ain't bad; the place when I got to use it was a 3-week temporary gig for me (they needed additional programmer for emergency fixes). The places where I was actually employed all used Skype, and "bearable" is the best I can say about it.

I think the best solution would be a Hipchat/Slack-like IRC client.