KDE is mainly known for producing the KDE Desktop Environment (used in Kubuntu) for Linux.
Active community for UK based Audi TT owners. Almost 30k members and 2 million posts, complete with unique style & powered by 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.
Boasting almost 14 million posts, Ars Technica is one of the biggest and oldest technical forums still operating today. They use phpBB to power their forums and comment system.
OpenCart is popular, powerful, and easy to use shopping cart software. Their healthy community forums are powered by phpBB.
Inspired by Max Berry's book, Jennifer Government, NationStates is one of the most popular online simulation games. The forum boasts over 5 million posts and 200,000 users.