CMS Detector is a PHP class that can detect the software used by a site by analyzing its HTML. It takes as input the HTML of a given page and checks if certain HTML tags are present in the page, which usually are associated with certain Web applications. The class returns the list of known applications that seem to be used in the site, as well the URLs of those applications.
CS-Cart is a turnkey shopping cart solution that includes all necessary features to build a successful online Web store. It is ready to use right from the start. With its functionality you can start an ecommerce Web site of any complexity: from a one-product shop to a full-featured online store.
Chyrp is a blogging engine designed to be very lightweight while retaining functionality. It has powerful theme and extension engines, so you can personalize it however you want. The code is well-documented, and it has a very strong structure that's loosely based on the MVC design pattern. Chyrp allows importation from several different blogging engines and uses a system called "feathers", which are basically templates for custom posts.
Cocomore Drupal Core is an enhanced version of Drupal 6.x Core that integrates all of the speed and scalability improvements from, and adds an "Intelligent Routing" expansion of Pressflow's support for database replication, full integration into Drupal's update mechanism, more efficient cache management, and Memory Threshold and Session Starter debug tools.
Coffeemade is a CMS for PHP developers that lets you define the data you need managed, like a set of books with title, cover, etc. Afterwards it offers a simple interface for a Webmaster to add, update and rearrange books. You can then use the data however you want, via a small set of PHP functions.
Contao is a content management system (CMS) for people who want a professional Internet presence that is easy to maintain. The state-of-the-art structure of the system offers a high security standard and allows you to develop search engine friendly Websites that are also accessible for people with disabilities. Furthermore, the system can be expanded flexibly and inexpensively. It features easy management of user rights, a Live Update Service, a modern CSS framework, and many integrated modules (news, calendar, forms, etc.).