KDE is mainly known for producing the KDE Desktop Environment (used in Kubuntu) for Linux.
It is the Italian Community for Ubuntu, a popular open source community operating system based upon the the Debian Linux Distribution.
Fujitsu is a hardware and IT services company focused on providing IT-driven business solutions. Their community forum is powered by phpBB.
VirtualBox, developed by Oracle, is cross-platform x86 virtualisation software. It has become one of the most widely used virtualisation solutions in the world.
Adblock Plus is one of the most popular Firefox Add-ons in the world, with over 10 Million daily users and over 100k downloads a day. They use phpBB to offer support to their users.
OpenCart is popular, powerful, and easy to use shopping cart software. Their healthy community forums are powered by phpBB.