- Tab Mix Plus - a great plugin that consolodates a lot of the tab customization options into one handy plugin! I highly recommend this one.
- Foxmarks - Let's you synchronize your bookmarks across multiple computers.
- Fasterfox - One click optimization of some of the more fiddly settings to increase performance.
- Compact Menu - Allows you to get rid of any menus you don't want.
- Firesomething - A silly but fun extension that allows you to randomly generate silly names for the browser such as "Moozilla Lightninglizard".
- Google Reader Notifier - Notifies you when you have new feeds in your Google Reader account.
- Roboform - an automated form filler which can fill in your name, address, Credit cards, etc from encrypted profiles which you create.
- Firebug - let's you view HTML and CSS in a browser pane and preview real time changes to the code.
Tons more to be had by clicking Tools>Extensions and then the "Get More Extensions"
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