This thread is for ideas for new vending signs (hopefully in the future we will be able to put them in other places, like containers)
My ideas:
How about a sign for each crafting category, for instance: ceramics, cloth, sausages, etc. The icons already exist, and they do a pretty good job of breaking up the various goods
A coin sign, for moneychangers
A misc sign
Also, perhaps a roman numeral level indicator could be used to show the value of the items, similar to creature level. This would be subjective for merchants, but in towns (assuming it can someday be applied to containers) it could be useful for separating objects by quality. (helpful for thieves, too)