Ruby on Rails became a popular web application framework because of how easy it promotes the rapid prototyping methodology used by web developers in rapid development.

Of course, being an open source project also helped Ruby on Rails establish itself as one of the most popular web development tools as well.

New developers often get caught up working with PHP over Ruby on Rails because so many applications are built using the PHP language like WordPress, Joomla, Wikipedia and others.

Because of its popularity, PHP has become one of the most popular “tools” for web developers and Ruby on Rails is often overlooked as a result. However, it is a bit unfair, and ignorant, to compare PHP to Ruby on Rails since one is an actual programming language (PHP) and the other is framework (Ruby on Rails).

To level the playing field, let’s take a look at some of the best sites built with Ruby on Rails:

1. Basecamp

The project management site that started the Ruby on Rails phenomenon.

2. Scribd

Using Ruby on Rails to help the world read, discover and share.

3. Hulu

One of the most popular places to watch your favorite TV shows, movies and Internet videos.

4. CrunchBase

The go to database for the tech companies, people and investors.

5. Slideshare

Share your slide shows with the world to educate, inform and even market your company, products or anything else.

6. Funny or Die

Will Ferrell and team’s humor site.

7. Zendesk

This customer support site turned to Ruby on Rails to help organizations better connect with their customers’ needs when it comes to support.

8. Github

Collaborative social coding hub for to better organize teams.

9. Yellow Pages

The online directory that replaced the phone book and saved millions of trees.

10. MedHelp

Online community focused on health and medical issues.

11. OneHub

Online collaboration portal for sharing files and managing your web development projects.

12. Freckle

Time tracking made simple with Ruby on Rails. Use this as a developer to track time spent on projects or look to it for inspiration.

13. Chowhound

Home to the popular food based message board where visitors can share tips related to dining, eating and food shopping in a local area.

14. Bleacher Report

Want to see how RoR can be used to develop a site that leverages user created content, look no further than Bleacher Report. This site allows users to upload articles and slideshows for other visitors to read and comment on.

15. Corkd

Some sites developed with Ruby on Rails are just for fun. Corkd is a social network connecting wine lovers from all over the web.

16. CrazyEgg

Better user experience comes from testing and data. CrazyEgg creates a heat map of your site showing where users have clicked so you can develop sites that visitors find useful.

17. Get Satisfaction

Allowing businesses to build communities where customers can speak up and businesses can build better products. Lean start-ups find this site especially useful for developing products based on their customer’s needs.

18. Jobster

Turning to the power of Ruby on Rails, Jobster allows visitors to search all of the different job site at once.

19. Twitter (in the early days)

One of the biggest social networking sites there is and probably the most famous of all RoR sites. Twitter has since abandoned Ruby on Rails citing concerns with scalability.

20. 43Things

The largest goal setting community to help people set and meet their goals while being encouraged by other members.

If you have any you think that I left off this list, please feel free to include your thoughts in the comment section!