How to unpack a .deb file on Mac OS X without installing it

If you use Xcode, a utility called ar is installed. You can run the following command:

ar -x path/to/filename.deb

If you don't use Xcode, you could also install ar using Homebrew and run the same command.

Alternatively, you could use Homebrew to install the dpkg utility which has many more options to work against .deb files.

dpkg -c path/to/filename.deb