I used to be in the Navy and served on subs. I was hanging out with the knuckledraggers one afternoon when they were doing maintenance on torpedo tubes, and noticed the excess grease coming out of the zerk fittings looked really familiar. I knew that the design of the grease tube cartridges left a couple of ounces behind, so I asked them to give me the next tube they threw away. I took it home and compared it to the tube of Phil grease that I had, and it was identical in color, texture, and smell. From that point on, they would give me their spent tubes of grease, I'd cut open the other end and put the remnants into a clean paint can, and that's the grease I used for the next decade.

Good stuff.