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The only major exception is self-extracting archives (essentially .zip files that are packaged with a little unzip utility so that they'll open on a Windows computer that doesn't have a zip utility). I think Stuffit will open those. Likewise, File Juicer will crack open (or, erm, juice) any .exe file and try to extract components in it, if you want to extract an embedded CAB file, image, etc, etc.
 
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