I tested this with Stuffit Expander 7.0.3, but my guess is that you can use almost any version. It doesn't work with Panther's built-in zip-extractor ( BOMArchiveHelper) - so don't double-click the file, but choose 'Open with > Stuffit Expander' from the contextual menu (control-click on the file). Just rename the file extension to '.zip' (and confirm the dialog), and open it with Stuffit Expander. exe file! For instance, a PDF manual from Canon's site - they tell you to open it with Acrobat, but they made it an exe, saving just 0.2 MB. But you HAVE to have its contents, and you just can't open that. Sometimes you encounter a file on the Net which is compressed as a self-extracting zip-file for Windows only.