In Finland they are making things of empty coffee bags. Coffee is sold in thick plastic bags.
When the bag is empty, it folds into a flat, square piece of tough plastic one can sew and do different things with. In Finland they have been making hot mats and bags.
Here's how to make a hot pad: Kirsti-mummon pannunalunen
The bag can be made by first cutting and sewing the bags into strips that are then woven like a chip or shingle basket (split basket?). In Finland they used to make a lot of different things of birch bark.
Frolic is a quite nice blog... ;-)