Rather than the weirdness of a small scale, weird spell that can't work without N'ghelon's sphere/stone maybe something similar raised for market rumors?
A sizable tithe to some rumor monger at the Rumor Mill that lets you carry around a 5 pound brick that turns your Whispering Wind into Market Rumors ala the Rumor Mill's rumor sending system?
Playing around with rumors and etc is a very cool notion and it's so nichely used but I could totally see Retainers sniping one another in petty rumors or a Scribe of the Royal Archive throwing out rumors of ILL DEEDS of Retainers who are in need of chastising or etc.