Some good firefox extensions for coders

http://sixrevisions.com/tools/top-20-essential-firefox-add-ons-web-designers/
http://codeidol.com/internet/firefox/Web-Surfing-Enhancements/Spider-the-Web-with-Firefox/

List urls of all open tabs
https://addons.mozilla.org/en-US/firefox/addon/url-lister/

Open multiple location
https://addons.mozilla.org/en-US/firefox/addon/open-multiple-locations/

Bookmark all opening tabs quickly without any dialog.
https://addons.mozilla.org/en-US/firefox/addon/bookmark-all/

Select a number of links with a rectangle and open them all in new tabs or do other things with the links.
https://addons.mozilla.org/en-US/firefox/addon/SnapLinksPlus/

Another one:https://addons.mozilla.org/en-US/firefox/addon/multi-links/

Adblocker plus https://addons.mozilla.org/en-US/firefox/addon/adblock-plus/

snapshot

webdeveloper

firebug