Hackourlives posted a guide about enabling rar/unrar support in Fedora 13

To enable the support for .rar archive files, you need to install a package called unrar which is only available though the RPMFusion repository. To enable this repository first, paste the following in a terminal while being root, however if you have enabled it already then skip to next step!

  Rar Unrar Support For Fedora 13 Goddard