From Drupal and Moodle, right through to a Git versioning system and Perl modules on CPAN, we contribute back to over 175 community open source projects. This list is in order of the number of projects contributed to.
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Perl module which allows you to update your ZoneEdit (http://www.zoneedit.com/) dynamic DNS records.
Why can't my computer automatically show me things that will help me with what I'm doing, instead of making me search around for them? The goal of the dashboard is to automatically show a user useful files and other objects as he goes about his day. While you read email, browse the web, write a document, or talk to your friends on IM, the dashboard does its best to proactively find objects that are relevant to your current activity, and to display them in a friendly way, saving you from digging around through your stuff like a disorganized filing clerk.
A nodejs script that allows you to watch a folder for changes and compile the less css files into another folder.
Docvert is a web application which takes word processor files (typically .doc) and converts them to OpenDocument and clean HTML. The resulting OpenDocument is then optionally converted to HTML or any XML. This is done with XML Pipelines, an approach that supports XSLT, breaking up content over headings or sections, and saving those results to multiple files (e.g., chapter1.html, chapter2.html, ...). The result is returned in a .zip file. Docvert has a user-friendly interface, and it's easy to integrate with other software as it uses a simple REST-style interface. The XML produced is easier to understand and more structured than the WordML or .DOC formats.
Domain Name Registry System (http://sf.net/projects/dnrs)
The Shared Registry System is software (client and servers) for managing a domain name registry, and is most likely to be of use for managing a country TLD. The software was originally developed in 2002 to manage the New Zealand (.nz) domain name space.
Drupal (core) (http://drupal.org/)
Drupal is an open source content management platform, allowing an individual or a community of users to easily publish, manage and organize a great variety of content on a website. Equipped with a powerful blend of features, Drupal is able to support community sites, blogs, portals and more. This is Drupal's core, you can find the contributed modules page at http://ohloh.net/projects/3502.
The Drupal Console is a command line interface tool, to generate boilerplate code and interact with a Drupal 8 installation.
PHP library to embed any web service or page (oembed, opengraph, etc)
Perl CPAN module for fixing up data which contains mixed encodings (ASCII / UTF-8 / latin-1 / CP1252) and outputs clean UTF-8