
The simple way to answer this question is to ask “What do you need it to do?” Most likely, someone in the Drupal community has developed a similar site with similar functionality. Often, the most common features and functions are embodied in modules contributed and freely available for download.
Drupal has been used to create simple brochure sites, providing a simple web presence for an organization or individual.
Drupal has been used by organizations to engage their publics through blogs, social networking, voting and more.
Drupal has been used for complete e-commerce sites, using a wide variety of payment and product delivery systems.
Drupal has been used as a platform for complete web applications.
On to Who uses Drupal?