I currently use BottomlessBag but it seems like it's no longer being maintained and it has some bugs.
The purpose of the mod is to help manage looting by comparing the value of loot items with items in your bags. It uses WowEcon or Informant to determine vendor/auction prices. Then, if your bags are full and you try to loot an item of higher value than something in your bags, it will ask if you want to replace it. If you have nothing of lower value, it will display a message saying that there is nothing of lower value to delete.
This is really useful if it works. The problem is that it is saying there is no item of lower value even when there is (and it even shows the values of both items in the message). I've posted about this on Curse.com and others have too, but there hasn't been a response and the mod hasn't been updated for a long time.
Since there seems to be an Ace replacement for just about everything, I figured I'd ask here. Is there anything like this?