Usually my away flag wards these people off, but sometimes it doesn't, and I have to politely tell them I'm busy. And I frankly refuse to respond to a repeated "Heya wassup?" from anybody whose name is something like SFKitty233. Unless, of course, SFKitty233 happens to be my colleague. Which she just might be.
Annalee Newitz is a surly media nerd who is probably messaging somebody on IM right now.