Export Illustrator Layers as PNGs | Matthew Ericson – ericson.net http://www.ericson.net/content/2010/10/export-layers-as-pngs/
Export Illustrator Layers and/or Artboards as PNGs and PDFs | Matthew Ericson – ericson.net http://www.ericson.net/content/2011/06/export-illustrator-layers-andor-artboards-as-pngs-and-pdfs/comment-page-2/