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.
GameServers is a premier Game Hosting company, having collaborations with big names such as Infinity Ward, Treyarch and Epic Studios.
Info-Mac is a community dating back to 1984 as a mailing list and was the first online community for Apple's Macintosh computer. All of their content was converted to phpBB in 2007.
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.
It is the Italian Community for Ubuntu, a popular open source community operating system based upon the the Debian Linux Distribution.
Solia Online is one of the most active online communities with over 18 million posts. Solia Online allows you to create your own avatar, buy items, and discuss topics with your friends.