100 places everybody has been and nobody can find on a map. Rock Bottom, Cloud Nine, the Middle of Nowhere, Wit's End. Each one painted as though it were a real town.
Every card carries where the phrase came from, and most of them came from somewhere specific: a swimming pool, a mine shaft, a Civil War telegraph line, a 1941 cartoon in The New Yorker. None of the towns exist. All of them are free to send.