Spaghetti Parenthesis Visualizer is an in-browser (meaning that it doesn't send your code to a server) tool that takes deeply nested conditionals in languages that follow in C's footsteps, including Python, Perl, PHP, and Java, SQL queries, or some Lisp code, and provides two visual presentations that clearly and cleanly display how deep each part of the code is in the layers of nesting.
Squarebase is a Web-based interface for MySQL databases. The basic idea is that it builds a database (called the "metabase") that describes the structure of the database. The information in the metabase is used to format lists and forms for browsing and editing the contents of the database.
documentr is a Web-based tool for editing and presenting software documentation. It allows you to easily maintain documentation for multiple products and product branches. Edits can easily be copied between branches, with merge conflicts being handled gracefully. It uses Markdown as its markup language, along with some extensions, and has a role-based permission system.
ezContents is a Web site content management system in the form of a Drupal distribution. The default theme is fully responsive. Its features include maintaining menus, adding authors that write contents, permissions, workflow, and layout possibilities for the entire look of the site by simple use of settings. A @font-your-face module with Google Web Fonts is added by default. It offers great flexibility for the Web site developer and a user-friendly interface for the editor. You can extend it yourself using existing Drupal modules or themes.
phpDays is a flexible PHP 5 framework for rapid Web site development. It features an MVC architecture, Ajax support, YAML configuration, database abstraction (MySQL, PostgreSQL, MS SQL, etc.), a good collection of standard models, an excellent quick start guide, and logging to files or firephp.