ToolbarBrowser - FREE Search Toolbar
Firefox SEO Toolbar Extension with Website Ranking Features
The SEO Toolbar is fully customizable. You can change its location easily from the options menu and even move it down on to the statusbar. There are several different views available, including icons and text, icons only or page ranks only (PageRank, Alexa Rank, PI Rank, Compete Rank and SEMRush). You can even hide ranks you don't wish to see. See the screenshots for examples of different views.
Server header view and search engine view are handy tools for any web developer or SEO. Server header view will help you identify any security risks or issues with your webserver. Search engine view can be used to help optimize your webpages for search engines.
The toolbar includes handy shortcuts to popular PPC Engines, SEO tools and forums, Keyword Research tools, and domain tools, including (just to name a few):
Mozilla Firefox 1.5 - 4.0
To go to the config screen, press Help drop down list and choose Options. You will have several choices on the option, such as toolbar placement, option to show only page rank buttons on the toolbar and to open all new windows in a new tab instead.