Pixelmator is a popular commercial image editing software for Mac OS X users.
GameServers is a premier Game Hosting company, having collaborations with big names such as Infinity Ward, Treyarch and Epic Studios.
As the official board for the world-famous band Queen, this community hosts a wide variety of discussions by Queen fans from around the globe.
KDE is mainly known for producing the KDE Desktop Environment (used in Kubuntu) for Linux.
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.
The Raspberry Pi is a cheap, credit-card sized computer. The official website uses phpBB for their discussion forums.