One question I’ve heard pop up more than once at local WordPress Meetups and at WordCamps is whether WordPress can be used as a CMS or not. My basic response to them is that WordPress IS a CMS but if it doesn’t have something you need out of the box, chances are good that a plugin exists to fill in the gap. Granted, if Joomla or Drupal provides most of what you need out of the box, then you should use the right tool for the job.
Thankfully, we have sites that go out and compile these lists of plugins for a specific audience. Noupe.com has a list of 40 exceptional plugins you can use to turn WordPress into one heck of a powerhouse CMS.