blatant self-promotion
So if you're working in a corporate environment where the in-house messaging of choice is Microsoft Exchange Instant Messenger, but you're not inclined to use a Windows machine, please to be availing of my RVP (Rendez-Vous Protocol?) plugin for Gaim 1.0.1 (and possibly upward) which will allow your Linux machine to talk to such a system. Also, quite possibly, your Mac. I'm still working on the latter. Actually, I lie. I'm fiddling with the file transfer code, and the Mac option is dependant on me hassling a cow orker for access to his machine during non-office hours.