I couldn't find a thread for free chassis materials that can be commonly found, but I've thought of a couple examples. I was just in a home improvement store (Home Depot) and found these 2 free items. 1) Paintsticks- totally free. 2) In the kitchen display area, there are laminate countertop samples, some of them are 3 1/2" x 5". Please expand on this post and list any free materials that can be commonly found. I'll stay on the lookout and post it here, too.