Pacifist has existed for years as the main utility on the Mac for exploring .pkg Installer Packages on Mac OS X and extracting files from them. You can also use it with .dmg disk images, and .zip, .tar, .tar.gz, .tar.bz2, and .xar archives. This is particularly useful if an application installed by Mac OS X becomes corrupted or needs replacing for another reason. Rather than reinstalling the entire Mac OS X, you can just replace what you need to – and it’s easy with Pacifist. You can also use it to browse the kernel extensions installed in your system and it lets you see what installer installed them, and whether the installer was made by Apple or a third-party. It’s just $20 shareware and it’s available directly from the developer CharlesSoft.
The interface is easy to use, giving you the option of opening a package, URL, Apple installers or searching installer receipts. I decided to try out browsing the Mac OS X Mountain Lion Installer app which I keep on my boot drive and backup drives (to save myself having to re-download in the future or rely on the Recovery partition or Internet recovery).