Ok so you have this new awesome weapon that you're saving materials for. You only need the recipe/a bit more energy/that one last component to make it. You decide to play some more later for whatever reason. You come back and check in your materials folder only to not remember what you were saving that Rocket Sprocket for.

My suggestion is that the player can make folders inside the folders he already has to organize his things a bit better. He could drop his materials for his future Pepperbox in a folder inside his materials folder and name it accordingly. He could drop his now obsolete Punch Gun in the folder with the others to make his inventory a bit less cluttered.