firefox add-ons

As a developer I use firefox add-ons to ease my web development. But as the number of add-ons are countless and not every add-on is usefull here is a list of add-ons I use the most:

1. delicious: https://addons.mozilla.org/en-US/firefox/addon/3615
   
2. Web developer: https://addons.mozilla.org/en-US/firefox/addon/60
3. cookie swap: https://addons.mozilla.org/en-US/firefox/addon/3255
4. firebug: https://addons.mozilla.org/en-US/firefox/addon/1843
5. colorzilla: https://addons.mozilla.org/en-US/firefox/addon/271