There is a certain kind of modernist story that involves the sudden appearance of an inexplicable thing in an ordinary social situation -- something ususlly large and unavoidable -- that's not particualrly threatening but is inconvenient and eerie. Gradually people come to either accept it or explain it to themselves. Eventually it vanishes, or it never does. The only example I can think of is Marques's "A Very Old Man with Enormous Wings." I know there are others. ANy examples?