OpenOffice.org offers a free and fully-featured office suite which meets the needs of the common consumer all the way up to large enterprises.
It is the Italian Community for Ubuntu, a popular open source community operating system based upon the the Debian Linux Distribution.
A very active community for a KFAN-AM, a popular sports radio station in Minneapolis/St. Paul, MN.
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.
The Raspberry Pi is a cheap, credit-card sized computer. The official website uses phpBB for their discussion forums.
Fujitsu is a hardware and IT services company focused on providing IT-driven business solutions. Their community forum is powered by phpBB.