I created a LinkedIn clone for specific use for athletes in Django. The application has three different types of users - recruiters, athletes and mentors. Athletes can logon, maintain their profile, see their college connections and apply for jobs. Recruiters can search athletes, post jobs, network and message athletes. Mentors can maintain their profile, search athletes and send messages.
Django has a very large ecosystem of plugins and it is easy to implement new plugins. Coupled with the ease of development around the model-view-controller framework and built in ORM, Django lets you move really fast. I really like the static-assets plugin that maintains all of the project assets through a site like Amazon S3.