There are a host of add-ons that you can – well – add on to the Firefox broswer that can help you monitor the activity of your site. Below is an incomplete list of Firefox add-ons.
First you are going to need the Firefox browser if you don’t already have it.
Firefox is an open-source browser. What that means is that you or I can modify how it acts on the internet. This isn’t possible with Internet Explorer. Firefox has been able to open up their code so other developers can modify and in turn enhance your web experience. I highly recommend it
SEO for Firefox
From SEO guru Aaron Wall, SEO for Firefox lets you "See important competitive research and search engine marketing data directly inside Google and Yahoo Search Engines. Install it here
Check out your PageRank and even get an idea of traffic to your site in your browser. Click on the Snapshot link and you will be taken to Competes site where you can measure your site against other sites. Get it here
These are just a few to get you going and we will have a more exhaustive list as more and more of these become available