Kissing cousin to the more famous Theremin, the ondes Martenot was immensely popular upon its release in 1928. Far easier to play than the Theremin, but producing a very similar sound, it was immediately incorporated into the Western art music of the time by composers such as Olivier Messiaen and Edgar Varèse. More recently, it’s been used by Radiohead guitarist Jonny Greenwood, who has featured the instrument on each of the group’s albums since 2000’s Kid A.