WebsiteCompressor is a tool to streamline HTML code generated by WYSIWYG-HTML editors. It has also image converting/recompressing capabilities, including batch converting of image files from various formats to JPEG.
Most programs add lots of characters to format or comment HTML code they generate. Suddenly you got files occupying 65 KB when only 45 KB would accomplish the same. Although browsers ignore this superfluous data, Web servers still have to transmit these bits and bytes, which inevitably adds up to the overall download times.
WebsiteCompressor is available for US$20. You can find more information and a trial version at Blue Line Studiosi site.