For BarCamp, we are using a web based chat program called Pibb. It's made by the good folks at JanRain, who have done some amazing work on OpenID. Using this identity backbone, they also created a fun site called Jyte for asserting and voting on claims. But the thing I'm really stoked about how they integrated IRC through a bot. For years we've begged for a simple web based client for IRC, partially because nobody knows what IRC stands for or what client to download or how to set them up.
You can read about this on their blog. If you want to find something to volunteer for, do it the good old way with IRC #barcamp, or go sign-in with your OpenID and jump into the Barcamp channel.
No, I didn't say IRC 2.0.
