With the RnR PPTools Optimizer, you can optimize your PowerPoint presentations for a variety of uses -- email, web, laptop/desktop shows, printing, even pre-press and 35mm slides. The Optimizer automatically makes a copy of your original presentation and includes only the amount of image data needed to optimize the presentation for the specific use you chose.
More information about the Optimizer and other PPTools is available at http://www.rdpslides.com/pptools/