I'm certain now that "This item is used in quests" is a default message to posted items. Otherwise, it should truthfully say "No one knows wtf to do with it atm". = P
Every so often I 'donate' items I have to idea what they do to a NPC (if they don't say "I don't need this") or an inanimate object...So if you see this in an oven in some random town, you can blame me.
Maybe that hide-liking gnoll in ICO would want it...