a used toothbrush
I asked for specific stocking stuffers. I wanted to create a little "necessities kit" to keep at work -- emery boards, dental floss, toothbrush, lotion, etc.
Instead of buying the requested toothbrush, my husband decided to save a step and just include the toothbrush that had been put back in its packaging but that had been obviously used. He assumed it was my toothbrush, but it actually belongs to my sister (she keeps it here for use during her visits).