From Rainbow Software:
JPPG Cleaner is simple but powerful utility for cleaning JPG files from anything that is not picture data. Commonly used programs such as Adobe Photoshop are writing additional information into JPG file that isn't needed for correctly displaying the picture. Texts such as File written by Adobe Photoshop, Creator: Poly View; picture previews (sometimes even bigger than main JPG data.); Color Management data. All this data is useul only when opening the file in program that created it. Other programs such as Internet Browsers are just skipping this data, so the data is downloaded ant then thrown away. Just use this program when publishing JPG files on the Internet and your JPG files become smaller (if they contain non-picture data) with no quality loss.