1 Nanook of the North (1922):

The locals in Canada's Arctic Circle were captured in Robert J Flaherty's ground-breaking, silent documentary.

2 Grey Gardens (1975): Socialite shut-ins Edith Beale and her daughter in a conversational dance with the camera.

3 Fahrenheit 9/11 (2004): Michael Moore's brilliant exercise in post-9/11 Bush-bashing.

4 March Of The Penguins (2005): Oscar-winning ode to the waddling hordes of the Antarctic.

5 Kokoda Frontline (1942): Australian Damien Parer's combat footage helped the raw nine-minute film win the first Oscar for Best Documentary.

6 Shoah (1985): Claude Lanzmann's epic Holocaust tract concentrates on survivor testimonials.

7 The Thin Blue Line (1988): Errol Morris' film helped get an innocent man released from prison.

8 Don't Look Back (1967): The enigma of the young Bob Dylan on show.

9 Burden Of Dreams (1982): Werner Herzog stars in Les Blank's illuminating portrait of the fiery making of Fitzcarraldo.

10 An Inconvenient Truth (2006): Al Gore's alarmist, Oscar-winning lecture about the perils of global warming.