Webtrees is a PHP/MYSQL genealogy website creator which allows you to view and edit your genealogy online. It has full privacy functions, can import from GEDCOM files, and supports multimedia. It also simplifies family collaboration.
dabblet is an interactive playground for quickly testing snippets of CSS and HTML code.
List of web 2.0 sites, web services and tools
Drupal.org is the official website of Drupal, an open source content management platform.
Social networking in a box. Build a social network for your company, school, sports team or niche community all based on the power and flexibility of WordPress.
Joomla is an award-winning content management system (CMS), which enables you to build Web sites and powerful online applications.
Open source social communities
Open source adserver like Google admanager – Take control of your advertising