fp.board is a bulletin board software solution designed to both implement features of proprietary non-free solutions and provide exceptional security. It supports features such as a built in Markdown Engine along with BBCode, an advanced Ban Control Panel (modeled after IRC, with Account Exceptions and CIDR based IP bans), DNS Blacklist checks, checks against the StopForumSpam databases, and more. It has no issues with the Suhosin Patches, and is developed on a server that supports Suhosin.
NewsCloud is software you can use to power engaging social media communities. It provides a suite of Facebook-connected interactive features that can help you host a vibrant online community for your neighborhood, topic, community group, nonprofit, membership association, or city. While most content management systems are optimized around publishing, NewsCloud's features offer ways for your audience to participate and lead the site with user generated content. As activity increases, you can integrate advertising and paid content referral systems to capture new revenue streams. NewsCloud is designed to help you move beyond the limitations of Facebook pages.
TinyIB is a lightweight PHP image board which emulates the functionality of 4chan. If you use MySQL or SQLite, you can use it to create an efficient setup able to handle large amounts of traffic. If you don't use a database, it can store posts as text files for a portable setup capable of running on virtually any PHP host.