Ugh. I hate invisible mode on instant messenger. I have some friends that use it and I can never tell if they're on. It's totally fun to attempt to message them randomly to see if they are. Invisible mode is not much more than a glorified email mode. I know the "technical" reason it's there, but come on. The whole purpose of instant messenger, for the most part, is to be able to see which of your "buddies" is online and perhaps willing to talk. If you don't want to be bothered, set your status to away.