Marcel Duchamp passed away 43 years ago on this day. We salute and remember him. The classic 1966 BBC (Joan Bakewell) interview, excerpted above, may be seen in its entirety here (on the Dada Companion page (along with details on a variety of Duchamp interviews).
More rare BBC archival footage may be viewed here. More interview footage here and here. Perhaps the most useful survey of his career would be this - "Marcel Duchamp In His Own Words" (here, and with a second part, here). Also, essential (and en francais), Jean-Marie Drot's 1963 film portrait, "Jeu d'eches.." featuring an in-depth interview with the artist. (Also en francais, a late (1967) interview with Duchamp at the Givaudan Gallery in Paris). Interviews with Duchamp are always both enigmatic and revealing. These two 1959 audio interviews, both conducted in English (with George Hamilton and with Richard Hamilton (no relation!) prove the point. Similarly, well worth listening to is his paper, "The Creative Act" presented to the American Federation of Arts in Houston, Texas, in 1957. Robert Hughes' little survey of his career in "The Shock of the New" (tv series) and Duchamp's own classic 1926 Anemic Cinema complete this survey.