JFusion is a free GPL plugin for the award winning Content Management System (CMS) Joomla. JFusion provides universal user integration, by extending the Joomla 1.5.x - 2.5.x and with jfusion 2.x also Joomla 3.x user authentication framework without any core hacks.
With JFusion your users can login to both Joomla the software integrated by JFusion using the same username/password, the Joomla login even logs the user into all softwares. No core hacks are made which has the advantage that your can upgrade your software normally without reconfiguring JFusion.
JFusion also comes with a latest activity module, that displays the latest activity on the forum in Joomla and a login module that displays the forum avatar in a Joomla login module.
Jfusion also has features such as search module, who online and discussion bot.
JFusion does has bi-directional user-sync, which means that users can be both imported and exported from Joomla.
Some jfusion plugins also provide virtuel integration. Allowing you to display the content of a plugin inside joomla. Making it look like there are one and the same.