Salida de Bandera
Less a move and more a reaction to a move. A salida de bandera was originally an over-the-top-rope bump. Jerry Estrada was famous for his salidas de bandera, but the abuse he took shortened his career.
In recent years, most salidas de bandera actually end on the apron to set up another exchange, although occasionally the luchador taking the move will in fact fall all the way to the floor.