Earlier today I stumbled across references (using a Google search for another topic) to two secret preference panes that Apple has made, but hidden away and not installed by default.
The first preference pane is to change the Archive Utility.app’s (a daemon) preferences. This pane lives at /System/Library/CoreServices/Archive Utility.app/Contents/Resources. The pane is the topmost file and is named Archives.prefpane, just double-clicking the file will install it into the root /Library/PrreferencePanes folder and therein make it visible from the Other section of System Preferences.app. Once this hidden prefpane is installed properly you’ll notice that it has preferences to choose where to save expanded files/ archives as well as what to do with the archive or archived files after processing. It also has checkboxes for revealing the files/ archives in Finder and to keep expanding if possible.
The second preference pane is for Disk Image mounting and encryption. This pane lives at /System/Library/PrivateFrameworks/DiskImages.framework/Resources. The pane is named DiskImages.prefpane. Again, double-clicking this file will automatically place a copy into the root prefpanes folder and then you’ll be able to use it in System Preferences.app. This prefpane allows you access to change the Pre and Post Processing preferences for image mounting, as well as to or not to use your keychain for image encryption.
These two prefpanes may not seem like much, but they do allow user-level access to some preferences for OS X that most users would otherwise never know existed much less change. On top of that, these prefpanes are made by Apple, so they’re certainly trustworthy enough. Enjoy, Alex.