Im not sure if this has been thought of, I searched for it on the boards and didnt find anything, so here goes.
Could there be instruments in the game that you can buy, like Ocarinas, Flutes, small Guitars, just basic instruments that would fit in planeshift, these could be used to signal something, like an attack or maybe guilds could use them for secret signals, like when Robin Hood used his horn to call his men. It could also be used to gain money, people could go around as traveling minstrals, there are 2 ways this could work, you could either equip the instrument and have buttons assigned to notes, or you could \"learn\" a song, or possibly write one youself, and you equip the instrument and it plays it for you, but now, this adds another stat, and bath to go by, the minstril path and stat. If #2 were used, then you would need a certain stat lvl to be able to write your own music, which would simply go on a peice of paper for you to play later.