As far as file compression goes *.7z is one of the best. This application extends Windows' limited archive capabilities. I primarily use it for extracting archives that I download from the web. All Drupal modules and themes come packaged in a *.tar.gz ("tarball") archive, so I'm unarchiving a lot. The interface is very simple and uncomplicated. Extraction time is minimal, and the installer throws some nice options into the right-click context menu. I've never had many problems with 7-zip and it's a great piece of software, especially if you don't want to have anything to do with shareware alternatives *cough*winzip*cough*.

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