I'm a big fan of Firefox and I'm very happy to be contributing to this browser with my own add-on. Here are some people and projects that have inspired the creation of this toolbar. You also get a little history of how and why I made it.
SEOpen: I used to be a regular user of this extension but it wasn't actively updated anymore (last update october 28, 2006) and wasn't compatible with the newer Firefox 3.0 when it came out. After searching for similar add-ons, I couldn't find any of my liking, although a few were interesting (like SearchStatus), they all had lacks in some area that were frustrating, would slow down the browser and searching considerably or weren't made to provide easy access menus for often used functions like SEOpen. I even sent a message to the SEOpen creator to update his add-on, but never got a reply. I still thought SEOpen had the right approach for simple and easy access to routine tools, without slowing down Firefox, however.
So it motivated me to learn XUL and create a SEO toolbar in my free time, for my own needs, in september 2008. After it became palatable to a broader public, I decided to publish it in the firefox add-ons directory. Surprisingly enough, the SEOpen add-on was finally updated just a month or two after that. But Foxy SEO tool had become, in my opinion, a more complete add-on (better looking too :P ). It's also really nice to be able to update your own extension when you discover something new.
Web Developer: Obviously one of the greatest Firefox add-on for webmasters, as an open source project, it has been a great reference while learning XUL, although most of the code goes way over my head. Web Developer has been invaluable with the Search Spider Simulation feature in Foxy SEO Tool. I used to often check pages in Web Developer with functions like "Replace images with alt attributes", "Disable All Styles", etc, to make sure it looked good for the most rudimentary browsers, and was optimal for search engines. Many functions in Web Developer were used to build the Search Spider Simulation (thanks Chris!), which does something similar as all of them combined, but with improvements and modifications toward making it more specifically a search spider simulator, easily accessible in one single click.
Le Coin du Webmaster: Thanks to this webmaster site for the french localization. Although many functions of the toolbar are rather english oriented, I hope to cover a few more languages one day and maybe learn to access web services in other languages too. If you understand french, do pay a visit.