Anyone who does any type of modeling, be it scale, diorama, tabletop gaming, dungeon craft, trash-bash, and the like, knows the importance of a good bitz box. This is the stash of kitchen-trash plastic, old toys, plastic model sprues, and left over model parts, and misc cool-looking junk for use in your next build.
In this Miscast video, Trent talks about all things bitz box and how you can put together a worthy collection of bits and bobs while not spending too much money.
There are a lot of good ideas here, like putting together a terrain repair kit you can take (or give) to your FLGS (friendly local gaming store). Once you're on their radar as a good little munchkin, you can ask them to give you leftover sprue bits, broken models, and generally have them on the lookout for what you need. Trent also suggests talking to all of your friends with 3D printers to see if they'll save their failed prints for you.
Thumbnail image: pasukaru76 (public domain)