I was experimenting recently the couple Joomla/SMF to run a complete website with a forum, while there are many forums solutions for Joomla, I have found that SMF is an excellent alternative complete, powerful and free.

In reality I have found many websites opting for SMF as a forum solution for their Joomla website, you can notice it in the number of download of the SMF bridge for Joomla which is the higher one compared to other CMS such e107, Mambo, Xoops, iGamingCMS.