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.
wkhtmltopdf and wkhtmltoimage are command line tools to render HTML into PDF and various image formats using the QT Webkit rendering engine. These run entirely "headless" and do not require a display or display service.
Perl module to provide a programmatic interface to launching customised X Terminal windows
Xenia - FidoNet technology mailer/utils (https://sourceforge.net/projects/xenia-fidonet)
Xenia - FidoNet technology mailer, editor and utilities(original author: Arjen Lentz, BitBike / Lentz Software-Development)Prime objective: Linux port.
XFS Filesystem (http://oss.sgi.com/projects/xfs)
The XFS filesystem for the Linux kernel
These two modules help enable you to check if two XML documents are semantically the same. Some other modules try this but don't check namespaces. These modules check that the namespaces of each element (if defined) even if they are mapped to different prefixes. The XML::Compare module export the same(), is_same() and is_different() functions. The latter two return true or false (but no reason why) whereas the former returns true but throws an exception containing reasoning information if different. The latter _could_ be used as an assert statement in your code. The Test::XML::Compare modules enable you to use is_xml_same() and is_xml_different() functions in your unit tests as you would usually use Test::More et al.
This package in an implementation of the XML part of the EPP protocol, as described in RFC5730.
Simple API for XML including pure Perl parser
XML::Simple is a Perl module that makes it really easy to read and write XML files. It was originally developed for the purpose of reading and writing config files in XML format, many people find it useful for other purposes.
Zaqar OpenStack Queuing and Notification Service (https://wiki.openstack.org/wiki/Marconi)
OpenStack Queuing and Notification Service
Zen Kernel for Galaxy Nexus variants (toroplus/toro/maguro)