The vast majority of my work today is done in Drupal, which is by far my Content Management System of choice. You might wonder what is so special about Drupal, and why I would prefer it over other available CMS's (such as Joomla! or Wordpress). In my experience, Drupal is by far the most customizable CMS and has a vast community of very knowledgeable individuals who are constantly working to make it the most powerful content management system available. Drupal is so widely respected that hundreds of government websites have made the switch to Drupal, with new ones jumping on board every single year. Recently, the EPA announced their upcoming conversion to Drupal and NASA is currently considering making the jump!

Other well known websites running on Drupal are:

Popular Science
Warner Bros Records
How To Do Things

In fact, there are many more listed on the Drupal.org website. Click here to check them out.