public domain

Public domain materials are those things that have copyright or patent protection but have been placed on the Internet thus nullifying the protections. Like busting a condom, once it's done, it's done.

Making your entire lunch out of items other people at your workplace have discarded or explicitly said, "I'm not going to eat this. Does anyone want it?" An example could be a sandwich made from leftover bread and old cream cheese from that time two months ago when someone brought bagels in for everybody.