I saw this one on WoW Insider the other day and knew I had to bring it up. Here's the scenario, and I'm sure it has probably happened to all of you: Somebody asks in guild chat, "Does anyone have any X item?" and your response is "I think I do in my bank" or "on an alt". So, you make the trip back to the bank because they really need it. Or you log on with the alt for the same reason. "Oh wait," you respond, "I used them all yesterday." There's certainly got to be a way to be better organized.
There used to be a mod that I used called Character Inventory (or something like that) that would show you the bags and bank slots of all your toons. It was really nice because you could see your own bank even when out in the field. But the Add-on that WoW Insider recently highlighted seems to go even further, and better.
It basically inventories all of your items in bags and bank, and then you can do a search for the items. Take, for example, the picture I borrowed from WoW Insider. You can type in search criteria such as "silk". It will bring up all the items that have the word "silk" in them that you have on any of your toons (once Possessions has scanned them all). Then when you mouse over the items, it tells you which alt has the item, and whether it's in their inventory or their bank.
While this add-on seems like it would really help me since I can't remember what is in my bank... for people that constantly move items between toons, this would probably be a required mod. I haven't taken the time to install it yet, but I can certainly see the huge benefit that this mod will give you.
For those that want it... head on over to World of Warcraft UI / Mods to pick up this beauty.