Fireboard (http://www.bestofjoomla.com/) is a terrific forum with numerous features a few of which are:
The installation is simple. Download the
Fireboard_Forum_1.0.3_UnzipFirst.zip program package and unzip it as the filename says. You will find a file called
component_Fireboard_Forum_1.0.3.zip in the package.
Click on Extensions | Install/Uninstall in the menu, select the
component_Fireboard_Forum_1.0.3.zip file, and click on the Upload File & Install button.