XWiki is a WikiWiki clone written in Java that supports many popular features of other Wikis like the Wiki syntax, version control, attachments, security, and searching, but also many advanced features like templates, database and dynamic development using scripting languages (Velocity, Groovy, Ruby, Python, PHP, and more), an extension system and skinability, J2EE scalability, an XML/RPC remote API, statistics, RSS feeds, PDF exporting, WYSIWYG editing, an Office viewer and importer, and a lot more.
GNU Wget is a utility for noninteractive download of files from the Web. It supports HTTP and FTP protocols, as well as retrieval through HTTP proxies. It can follow HTML links, download many pages, and convert the links for local viewing. It can also mirror FTP hierarchies or only those files that have changed. Wget has been designed for robustness over slow network connections; if a download fails due to a network problem, it will keep retrying until the whole file has been retrieved.
With LinkChecker, you can check HTML documents and Web sites for broken links. It features recursion, robots.txt exclusion protocol support, HTTP proxy support, i18n support, multithreading, regular expression filtering rules for links, and user/password checking for authorized pages. Output can be colored or normal text, HTML, SQL, CSV, or a sitemap graph in DOT, GML, or XML format. Supported link types are HTTP/1.1 and 1.0, HTTPS, FTP, mailto:, news:, nntp:, Telnet, and local files.
GroupServer is a Web-based mailing list manager designed for large sites. It provides email interaction like a traditional mailing list manager but also supports reading, searching, and posting of messages and files via the Web. Users have forum-style profiles, and can manage their email addresses and other settings using the same Web interface. It has supports features such as Atom feeds, a basic CMS, statistics, multiple verified addresses per user, and bounce detection, and is able to be heavily customized.
PSX is a PHP framework for creating RESTful APIs. It helps you to build clean URLs serving Web standard formats like JSON, XML, Atom, and RSS. It includes a handler system that abstracts away SQL queries from domain logic, a routing system that executes correct controller method for the location of the controller and the method annotation, and a flexible data system that converts database records into formats like JSON, XML, Atom, and RSS. A lightweight DI container handles dependencies. The controller supports request and response filters that can modify the HTTP request or response, and filters are provided for Basic and Oauth authentication.
GroupOffice is a groupware suite that takes your office online, implementing online collaboration and CRM. It allows you to share projects, calendars, files and email online with co-workers and clients. It is easy to use and fully customizable. It also features synchronization with PDAs and Outlook.
album is a free HTML/XHTML photo album and gallery generator that supports themes/skins. You can choose different themes or write your own to get different layouts and styles. It creates all your thumbnails (including directory thumbnails) and descends into directories so you can organize your photos. See the home page for more examples. album is also multi-lingual, with many languages being added all the time. N.B.: The purchase link is provided for donations; the software does not cost anything.