"Murder by Proxy: How America Went Postal" : It starts out as a straightforward examination of why some U.S. Postal Service employees went on shooting sprees in the '80s. (The main culprits: managers who savagely harassed vulnerable individuals and pushed them to the breaking point.) But then, in a breathtaking leap, Emil Chiaberi's documentary argues that beginning with the Reagan administration, American workers havebecome ever more powerless; today so many of us feel economically trapped that we face an epidemic of "going postal". A fine example of spitting-mad, in-your-face filmmaking.