* – phpBB is one of the most popular forum softwares. With phpBB you can customize with mods and you can stylize your forum. For a fully Modded phpBB forum with about 500 different mods that all have been fully tested click here.
* – Vanilla is a lightweight open source forum that was developed by Mark O’Sullivan using PHP and MySQL. Vanilla comes loaded with extensions, and you can customize the forum with your own add-ons.
* – YetAnotherForum.NET is a Open Source forum or bulletin board for web sites running ASP.NET. YetAnotherForum.NET is fully coded in C# ASP.Net and uses Microsoft SQL Server. It comes with all the standard forum features and even WYSIWYG editors.
* – YaBB is an Open Source forum system (bulletin board, message board) written in Perl. This system is the first and most popular open-source perl forum software and it runs very fast.
* – IceBB is an open-source forum solution powered by PHP and MySQL. IceBB is written with the prototype and scriptaculous frameworks and the code output is very clean. IceBB has mostly all the same features as some of the paid forums but it even has an RSS feed.
* – WP-Forum is a simple discussion forum plugin for WordPress. It has three themes that you can choose from and is a simple solution if you have a WordPress powered site.
* – miniBB is an open source message board script written in PHP. miniBB is a lightweight and compact alternative to phpBB. With miniBB you can customize the software with add-ons and it is Search Engine Optimized.
* – SMF is a free professional grade forum software that actually isn’t open source. SMF has loads of features with a great community and tons of free modifications.
If you know of any more Open Source Forums then please comment below. Thanks!!!