We just installed two mods on the FF system:

Content Sharing
We've added a button to the bottom of all topics where your visitors can share the content via email or any of the social networking websites (digg, facebook, myspace, etc). This can be disabled via the "Mod Center"

Search Engine keyword highlight
This mod has been enabled on all forums and highlights the keywords someone searched for when they land on your page. This is similar to when you google something and view the cache.

Enjoy