The New Republic's Chris Orr, one of the best commentators around, came up with a ranking of the Coens feature films, and thought I'd do the same. Updated with the inclusion of Burn After Reading.
01. The Man Who Wasn't There (2001)
02. The Big Lebowski (1998)
03. Miller's Crossing (1990)
04. Raising Arizona (1987)
05. Burn After Reading (2008)
06. No Country for Old Men (2007)
07. Barton Fink (1991)
08. Blood Simple (1984)
09. Fargo (1996)
10. O Brother, Where Art Thou? (2000)
11. The Hudsucker Proxy (1994)
12. Intolerable Cruelty (2003)
Avoided: The Ladykillers.
It's a shame that The Man Who Wasn't There, the brothers' most moving (and I'd argue, personal) film, has become a footnote in their oeuvre.