I have to keep AIM and all the other Instant Messengers turned off. It's impossible to get anything done and chat. I don't even take personal calls on my cell until weekends. (I know it sounds stupid... but I have to tell friends not to phone me till after 7:00pm and on weekends.) Here, I can pop in and out when I'm between calls, done with emails, done with research, etc...
I have my international attorney on the only IM I keep active. She's just left on a year long around the world back pack trip with her new husband. I'm her emergency line while she wears holes in her boots.