Mouse oil
The other night, I was getting a bottle of vinegar out of the cupboard over the stove where we store our oils and vinegars. trilobites noticed that there were a few mouse turds up there. "Oh, great," we thought, "just what we need, mice getting into all of our food." After checking all of the other cabinets, including the ones with many bags of flour, dried fruits, and so on, we saw no sign of any mice in them, and we were busy, so we didn't do anything about it immediately but decided to clean it out and set a Havahart trap as soon as we got a chance. We also stopped at the general store to get some glass containers for storing our flours and sugars, in case mice did manage to find them.

Well, today we had a chance to clean out the cupboard, so I took each bottle out and gave to to trilobites to wash off, while I cleaned up the turds that were in the cupboard. There were quite a lot bottles; we like having a good selection of oils and vinegars on hand. As I was going through them, I noticed a stray cap lying there. "Huh, where'd that come from?" I worked my way further back, and then noticed that the cap was missing from the peanut oil. And the threading and plastic mouth had been chewed off. And in the bottom of the bottle, submerged in peanut oil, was a dead mouse. I guess that explains why I hadn't seen any evidence of him having gotten into the other food.

Anyhow, that's generally not something you expect to see every day. It's a good thing we noticed the turds and started cleaning up; I can only imagine what would have happened if I'd reached for the peanut oil without being prepared for what was inside...