With the recent release of Firefox 3, we got a new and improved browser of choice. The main reason I have been using Firefox for years now is expandability achieved with the Firefox Add-ons. There are a couple of add-ons that I can not imagine browsing without. They also help me do my job (WordPress and SEO) in a much efficient way.Firebug - this is most obvious reason I am using Firefox. It allows me complete control over site's CSS, HTML and JavaScript.