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.
A very active community for a KFAN-AM, a popular sports radio station in Minneapolis/St. Paul, MN.
KDE is mainly known for producing the KDE Desktop Environment (used in Kubuntu) for Linux.
The Raspberry Pi is a cheap, credit-card sized computer. The official website uses phpBB for their discussion forums.
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.
Gentoo Linux is an open source operating system built on top of the Linux kernel and based on the Portage package management system.