Builders Bag (3.5e Equipment)
From D&D Wiki
Builders Bag: A normal looking study backpack that grants a limitless supply of vaious building materials and tools that only the wearer can use. None of the supplies that the bag can produce can be sold. Materials that come from the bag can not be dispelled and act as normal items for the most part. The bag also acts like a void hole in the fact anything put inside will be instantly destroyed.
Strong transmutation;CL 10; Knowledge(Architecture and Engineering)(Int) 10 ranks, Craft Wondrous Item; Cost 125,000 gp; Weight: 50 lb.