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.
KDE is mainly known for producing the KDE Desktop Environment (used in Kubuntu) for Linux.
Professional online broker and trading community.
The Raspberry Pi is a cheap, credit-card sized computer. The official website uses phpBB for their discussion forums.
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.
Waze is the world's largest community-based traffic and navigation app. Join other drivers in your area who share real-time traffic and road info, saving everyone time and gas money on their daily commute.