Very handy tool. I use it (not as much as I should) to see if my opinion, cite, or other planned contribution has already been aired. More than half the time, when I'm 50+ posts behind, I have nothing to add.
couple of decent FreeeRepublic extensions. I use Opera. It uses chrome and it works fine
http://cynwoody.appspot.com/fr_posting_form_enhancer.html
http://cynwoody.appspot.com/fr_tree_viewer.html
compliments of freeper - http://www.freerepublic.com/~cynwoody/
I think tree view is great for these “Q” threads