Here's a simple feature that I would greatlly enjoy.
I know that it would only cater to a minority of players, but still ..
I'd like to be able to farm while listening to my "dancing among the flowers fine" music box.
So, it would be rad if the possessed music box's music could be set to play overland.
Of course, to avoid trolls launching 1000 boxes at the same time, as well as to avoid lag, they would only play for the player using it, having no effect on any other.