Well, it's a Chatterbox :-)
in reply to YACR (Yet Another Chatterbox Request)
But I think it could be a solution, to allow reg. users to send messages to each others, so e.g. when you visit your home node, you (and only you) will see alist of messages, others have sent to you, and you can reply on them. Each message might bear a checkbox "delete" which might be unchecked to keep the message until the next session, so one day you get tired of unchecking and these messages will be removed. All in all, this is what e-mail does, but here it would only work on "localhost" somehow.
but all decision is left to your taste