Net-a-Porter's new Runway By Designer feature is the closest we're going to get to shopping directly from the runway. Choose your favorite designers, say Stella McCartney or Bottega Veneta, and peruse their Fall '07 runway shows. When you see a look you like and are willing to put your money on, click on it and bring it home. Now you're on your way to being the cyber version of Anna Wintour or Corine Roitfeld. Not a bad ...