i'll have to think about this one - I see it as quite a cool feature to have. My current line of thought is to do it via the InteractiveObject system, or a very similar system. The idea being you would place the object in the scene as per usual, but then define a new location for it to travel to, along with a movement speed, and then linger time. The server will then do the work of working out when it's moving etc, and send that down to all players nearby, just like how the interactive object system works.
I'll get back to you on this.