The Raspberry Pi is a cheap, credit-card sized computer. The official website uses phpBB for their discussion forums.
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.
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.
GameServers is a premier Game Hosting company, having collaborations with big names such as Infinity Ward, Treyarch and Epic Studios.
Pixelmator is a popular commercial image editing software for Mac OS X users.
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.