My former largest client (and now my largest source of referrals) operates entirely by IM. I found this out when, during a discussion with the CEO, he pulled out his cell phone and said "let me take care of that right now" and promptly started to use IM instead of voice.
And the W3C uses a terrific IRC client. It's tied into the teleconferencing bridge, and you can even take meeting notes online that automagically turn into properly-formatted minutes.
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And the W3C uses a terrific IRC client. It's tied into the teleconferencing bridge, and you can even take meeting notes online that automagically turn into properly-formatted minutes.