dead donkey

Meanings

1. A rarity.
2. A news item of no real significance, usually of whimsical or sentimental nature, placed at the end of a news bulletin or in a newspaper as filler. A dead donkey can often be removed from the programme or publication if a more significant story needs extra time or space.
3. Something useless on which time or effort is wasted.

Etymology

From the saying that no one ever sees a dead donkey, hence a rarity. This then became a stock example of a slow-news-day story, which was popularized by the title of the British sitcom Drop the Dead Donkey.