Mary Rose Barrington, a prominent member of the (British) Society for Psychical Research, labels it "JOTT", for "just one of those things", and has written a book about it. The case histories she provides are quite extraordinary, so I shall list only a few.
Some friends came from the city for the weekend and the lady brought with her a pattern and fabric so I could help make [a] dress for a party. One of the items was a long zipper and when it came time to put the zipper in, it had gone missing. She drove into a nearby town and bought another and the dress was finished. A couple of days after they had gone I was in my parlor and I looked up from what I was doing to see a wee man about eighteen inches high. He had brown skin and a very odd looking face. His hair was black and tousled like the hair of a baby. His eyes reminded me of apple seeds. And in his hand was the missing zipper. 'HEY' I called out and in that instant, he was gone and the zipper was lying stretched flat on the floor in the doorway. . . . I saw the little fellow clearly one other time while she [her toddler daughter] was playing with him.