Diffusion lines have proven again and again to be the most lucrative for fashion designers. Marc Jacobs has his own collection but its the Marc by Marc Jacobs stuff, the $12 canvas tote bags and $20 costume jewelry that really rake it in. Vivienne Westwood recently did a line for Nine West here in the States. Proenza Schouler and Erin Fetherston worked with Target's GO International. Isaac Mizrahi's Target items fly off the shelves. Most women can only dream of owning Chloe stacked oxfords or a
