There are items in AO that, if clicked generate text over player character. For example Library of Foul Language writes "Look at me!". So, there could be a new category in item shop for items with some texts. This items can be done very fast, doesn't impact power of player. I think, they can have demand in game.
For example I would like texts from Duke Nukem (Would they by in line with copyright law?). And please don't ruin this with price like 10$ per item. I see price somewhere under 0.1$.