Joomla is one of the leading open-source Content Management Systems. With a userbase of over 400,000, they use phpBB as a reliable platform for support.
VirtualBox, developed by Oracle, is cross-platform x86 virtualisation software. It has become one of the most widely used virtualisation solutions in the world.
Support for Synology NAS devices and ideas for future versions of the DiskStation software.
The Raspberry Pi is a cheap, credit-card sized computer. The official website uses phpBB for their discussion forums.
KDE is mainly known for producing the KDE Desktop Environment (used in Kubuntu) for Linux.
Zend Technologies is one of the largest and most popular companies producing a wide variety of tools and frameworks for PHP. Their community forums rely on phpBB.