Joomla Forums
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.
CitiesXL 2011
Developed by Focus Home Interactive, Cities XL 2011 is a city simulation game. Their community forums are powered by phpBB.
Sky Italy
Italy's home to the multi-national media giant, Sky. Sky's range of enterprises include digital television, broadband, phone lines, news broadcasting and sport broadcasting.
VideoLAN
The VideoLAN project produces the extremely popular VLC media player software. Their forums provide support for users of the software as well as the development community.