When I'm online, I am always set to "Away" so that I don't get flooded with people saying "HEY!" and the leaving.
I like to punish people who do that by inviting them to mass conversations. DON'T ABUSE THE AWAY BUTTON!
That is a fantastic idea. <3 I hate people who abuse the Away button. It's like, if you don't want to talk to people, don't clutter up their MSN lists.