FoxyTunes
Why bother switching to another application to manage your music player when you've got this awesome extension? This summer's update to version 2 added in a host of Web functionality, such as searching for artists, photos, lyrics, and albums on a variety of sites.
Tab Mix Plus
Don't like the new close button on each tab? Do you miss the multiple rows of tabs when they exceeded the width of your screen? This marvelous add-on can change those settings and almost everything else associated with tabs. Use your scroll wheel to browse through open tabs, or control tab switching via mouse gestures.
MR Tech Local Install
Not only will this extension-manager extension give you comprehensive control over all aspects of your add-ons, it can override the MaxVersionNumber of older extensions that haven't been updated for version 2. It's worth installing for the "Restart Firefox" functionality alone.
Download Statusbar
Download Statusbar takes the idea of the Download Manager, sticks it in a minimizable toolbar, and then tacks on some cool functionality. From the full mode, you can rename or delete downloaded files, or copy the source URL to the clipboard. Mini-mode changes the app to an unobtrusive progress monitor, with the full mode a click away.
Forecastfox
With this option-laden weather-monitoring plug-in, you can choose between Celsius or Fahrenheit, create different location profiles, and adjust if and how the extended forecast appears. There also are customizable icons, optional labels, day and night settings, and Forecast Fox even differentiates between today's forecast and current conditions.
All-in-One Sidebar
Firefox users who get accustomed to this wonderful extension rarely go back to the clunky default Firefox add-on window. From one clickable and customizable sidebar, you can access your history, bookmarks, downloads, extensions, and themes, as well as an endless amount of content via other extensions.
IE Tab
Extremely useful for those sites that require Internet Explorer and for testing purposes, this add-on loads any Web page as IE would display it, in the Firefox browser. A simple button in the Firefox status bar quickly and easily switches sites to IE and back. You also can specify some sites to always open with IE Tab.
Firefox Showcase
Despite some strong competition from Tab Catalog, this tab-thumbnail extension still gets our pick for its strong customization options and ability to show collections of tab previews in a variety of browser locations. One neat tip: clicking the scroll wheel on a thumbnail magnifies it.
StumbleUpon
As a social networker, bookmarker, and site reviewer rolled into one, this extension wears many hats. "Stumbling" takes one click and interactive icons make rating sites a cinch. Combined with the topic chooser, the additional one-click features give Web surfing a useful unpredictability TV just can't match.
Ook? Video Ook!
This extension for downloading embedded media is preferable to similar add-ons because it lets you go bananas with video. It offers one-click downloading, and it can save videos in their native formats-- Flash video, WMP or MOV. Also, it saves YouTube videos with their original file names or those of your choosing--not some nonsensical code.
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