As is traditional for a new Firefox release:
- Adblock Plus (hide ads etc)
- Adblock Plus: Element Hiding Helper (hide specific elements)
- DownThemAll! (download manager)
- Firebug (web development)
- Greasemonkey (custom Javascript)
- Screengrab! (capture web page as image)
- Secure Login (click to fill in login forms)
- Stylish (custom CSS)
- Post to del.icio.us (my version)
- OpenSearchFox (seems to have disappeared from the web?)
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I quite literally can't use the internet without Search Keys by Jesse Ruderman.
The opensearchfox listing does seem to be missing, but you can still install the extension from this url: https://addons.mozilla.org/en-US/firefox/downloads/file/21383/
via Biblical Studies and Technological Tools http://bibleandtech.blogspot.com/2008/06/firefox-3-getting-stuff-organized-add.html