Firefox Add-ons I Can't Live Without

I have discovered the world of Firefox addons. Not only do they make my everyday browsing easier but they have increased my programming productivity as well. By using addons such as FireFTP I can even get rid of programs like Cuteftp which was once a major tool in my toolbox.

Here's a list of addons that have made my life easier:
Firebug - Firebug integrates with Firefox to put a wealth of development tools at your fingertips while you browse. You can edit, debug, and monitor CSS, HTML, and JavaScript live in any web page...

FireFTP - FireFTP is a free, secure, cross-platform FTP client for Mozilla Firefox which provides easy and intuitive access to FTP servers.

WebDeveloper - Adds a menu and a toolbar with various web developer tools.

PlainOldFavorites - Use Internet Explorer Favorites directly from Firefox. No need to import, export or synchronize - the same Favorites appear...

Download Them All - lets you download all the links or images contained in a webpage and much more: you can refine your downloads by fully customizable criteria to get only what you really want. It also includes a speed accelerator.

NoScript - It stops JavaScript, Java and other executable content from running when you don't want it to.

Tab Mix Plus - Adds a lot of functionality to your tabs. Including multiple lines, duplicate new tab etc..

Tree Style Tab - This provides tree-style tab bar, like a folder tree of Windows Explorer. New tabs opened from links (or etc.) are automatically attached to the current tab. If you often use many many tabs, it will help your web browsing because you can understand relations of tabs. Use this in combination with above "Tab Mix Plus" for extra functionality.