Quest item is intended to solve the problem of where on earth did the item I just got for the quest go to in my bags. If you play "hunt your bags" for quest items this is the addon for you.
The idea is that you get what looks like an extra bag (it cant actually give you extra bag space sorry) but that only shows your quest items. If you open this bag you will only see quest items or items that begin a quest. This way you have only a single location to look in to view all the items you need for a quest. You need never again have to open your normal bags to hunt for quest items.
I plan to add features like warning you if you put quest items in the bank, showing quest items in the bag that are in the bank. Colour coding your bag items to highlight quest items, and any other useful feature in line with the goal of the addon that users suggest.
Use /qi show or /qi open to display the bag. Or use the FuBar plugin to click to open it.