Like a lot of people, I have one character that blacksmiths, another that enchants and so on. As I play, I pick up materials to benefit the others and bank them and, when on each character, withdraw their specific stuff.
So.... my enchanter picks up armour for the blacksmith. It would be FANTASTIC if I could tell with that character whether or not the other one needs it. That way, my enchanter could know what stuff he could simply sell off rather than banking everything (and clogging the bank).
Ideally, I would imagine it like a couple of existing research trackers that show icons in the inventory - this would just show it based on a different character's abilities.
This addon keeps track of each character's inventory.
http://www.esoui.com/downloads/info251-MobileBank.html
...maybe something can be done with research?