This would be useful for SL pets and bots.
I would like to be able to right-click on an object, and select "Chat" or something similar. Then a tab/window would open similar to local, group or ad hoc chat. This would need some form of marking to discriminate it from an avatar chat.
Messages I send in that window would be heard by the object (and all prims) but no others. The object scripts would be able to send messages to that window via llRegionSayTo(). If that window isn't open, the messages would be delivered in the current way llRegionSayTo() text is shown