Before Chairman Mao’s Little Red Book there was The Little Red Song Book, which included lyrics to rabblerousing ballads written by labor troubadours such as Joe Hill in order to organize the Industrial Workers of the World. A 1979 documentary about the IWW is being re-released on April 29, making the stand-up-and-cheer The Wobblies – as IWW members were nicknamed – the absolutely perfect film to see for May Day.