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.
Fujitsu is a hardware and IT services company focused on providing IT-driven business solutions. Their community forum is powered by phpBB.
Hugely popular Mozilla community providing support for Firefox, Thunderbird, Seamonkey and other well known Mozilla products. Over 350k members and 4 Million posts.
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.
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.
Professional online broker and trading community.