Adblock Plus
Self explanatory. The plus version you subscribe to a block list so you don't have to manually update the list. You can block specific images without blocking the other images of the same website if you wish. #1 add-on for Firefox.
Download Statusbar
Nonintrusive and minimal (in mini mode) compared to the default download manager
Extended Statusbar
Miscellaneous information on the status bar such as # of images loaded, time it took for the page to load, size of page
Fast Video Download
Rip YouTube videos and other embedded files
Fasterfox
self explanatory. Some sites won't load properly so you have load it again so you have to tweak the settings if it bothers you
Favicon Picker 2
Replace / create custom favicons in bookmarks/toolbar. For example, bugmenot has an animating favicon and it's annoying to stare at in my bookmarks toolbar. So I replaced it with a static version of the icon.
Flashblock
Cuts out annoying flash, I decide whether to load the particular flash content or not. Add homestarrunner.com in the whitelist.
Image Zoom
Zoom & resize any image on the page. Nice, but I haven't a practical use for it yet.
Image-Show-Hide
Useful if you're on a dial-up or tethered cell-phone connection and just want to see the page without loading the images. Save bandwidth.
Menu Editor
Cleans up the menu bar including context menus, I used it to remove "History" and remove unnecessary menu items. You can rearrange the menu, add separators.
MIME Edit
Tells the browser what to do when encountered with a certain file type
NoScript
Blocks javascript on untrusted sites. It takes a bit of work as some sites need javascript to work (any input box in Forums, flash-based sites...) so there's the "temporary allow site..." and "add to trusted sites" options in the status bar.
Organize Status Bar
Rearrange the status bar the way you like. You can even hide items if you wish. Very useful add-on.
Paste and Go 2
Copy url, paste & go.
Stop-or-Reload Button
Combines two icons into one. It just looks nice. Though if I wanted to reload, I press F5, and if I wanted to stop, I press ESC.
Stylish
Change the look & style of a website. I made YouTube minimalistic.
To get a slim extension list for Firefox 2: go here
Tab Mix Plus
Expands functionality of tabs. Plenty of options to choose from.
Titlebar Tweaks
I use it to remove "- Mozilla Firefox" on the titlebar.
Work Offline
Works exactly like in Internet Explorer. Isn't perfect as not all sites can be viewed offline even with my cache limit set to 500 MB.
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It's your browser. Configure it the way you want it. Internet Explorer an okay browser, but it doesn't do everything listed above.
