Firefox SEO Addons

SEOpen
http://seopen.com/firefox-extension/download.php
KGen 0.3
https://addons.mozilla.org/en-US/firefox/addon/4788
SEOQuake
https://addons.mozilla.org/en-US/firefox/addon/3036
SEO for Firefox
http://tools.seobook.com/firefox/seo-for-firefox.html
MetaTags 2.3.5.2
https://addons.mozilla.org/en-US/firefox/addon/1668
Web Developer
http://chrispederick.com/work/web-developer/