Multithreaded, unlimited categories and forums, moderators. Free.

Free and fully customizable message boards. Ad-supported.

Offers paid Ultimate Bulletin Board discussion boards.

Commercial discussion board provider. Features include content scanning, private areas and configurable look.

Provides free MyBB forum hosting. Ad-supported.

Offers free and paid customizable message boards. Free boards are ad-supported.

Free hosted discussion board service. Different layouts to choose from. Ad-supported.

Advanced website tools for building a variety of forums and message boards with optional marketing, advertising, and community features built in. Free.

Unlimited sub-boards with web-based administrative controls.

Forums are easy to manage, flexible, and can be graphically customized.