Jean Seberg's drop-dead sexy pixie cut in A Bout de Souffle by Jean-Luc Godard.Photograph: BFIEmma Watson waves goodbye to Hermione with a sleek crop.Photograph: Joel Ryan/APYoung British actor Carey Mulligan looks chic with a slightly longer pixie crop.Photograph: Ben Gabbe/Getty ImagesMia Farrow rocks an elfin do in 1967.Photograph: Alfred Eisenstaedt./Time & Life Pictures/Getty ImageMichelle Williams brings a cool platinum-blond twist on the pixie to the red carpet.Photograph: Rex FeaturesDid this haircut save The X Factor's Katie Waissel from the dreaded bottom two this weekend? She believes so.Photograph: Neil Mockford/FilmMagic