Facebook Group to WordPress
Pull your facebook group feed to WordPress
Plugin Tag: thread
Facebook to WordPress
Pull your Facebook group/page feed to WordPress
YATCP
YATCP allows you to have threaded comments (i.e. reply to existing comments) in your wordpress.
Woocommerce Support System
Give support to your WooComerce customers with this fast and easy to use ticket system.
vBPress
vBPress seamlessly integrates WordPress with vBulletin