"Stuffit Expander itself has a surprisingly spritely looking drag-and-drop front end, with built-in disk image mounting, virus scanning and the ability to map different file types to different archiving applications.
SmithMicro, the makers of Stuffit, don't give away the Expander free for ideological reasons. They give it away to enhance the value of their commercial products. It's a savvy move and one that's worked for many years. If you have one extraction tool on your machine, it might as well be Stuffit Expander – it handles most archive formats, looks great and works unobtrusively."