An excellent idea! In fact, I've just implemented it in my pmchat client (node has yet to be updated) :) If the user option of "away" is set, anonymous access (no cookies) is used to pull Chatterbox messages (and my client won't pull Private messages until you unset "away").

If we could then implement, as per Tye's suggestion, that the XP ticker and Private Message ticker don't update Other Users we can then have 24/7 clients that don't make people appear in the user's list all the time; which is one of the problems I have leaving a CB client running: I get messages (non-private) directed at me and I'm not even in front of my 'puter.