it's tagged extensions

Split - Chrome Web Store

Splits the screen, so you can surf the 'net with a friend.

https://chrome.google.com/webstore/detail/aeaf...

Ghostery

Ghostery scans the web pages you visit to find web bugs. Web bugs are used to track your behavior on the web in order to help the sites you visit to understand their own audiences and to allow advertisers to target ads at you.

http://www.ghostery.com/

Everything about Firebug - 21 22 Great Resources ยป Blog at veanndesign.com

Firebug is an excellent Firefox browser extension that is great for troubleshooting, editing, monitoring, and debugging.

http://blog.veanndesign.com/2008/04/12/everyth...

iMacros for Firefox

Any combination of browsing, form filling, clicking and information gathering can be recorded into a macro and iMacros even assists you during the recording with visual feedback.

http://www.iopus.com/imacros/firefox/

mozdev.org - platypus: index

Platypus is a Firefox extension which lets you modify a Web page from your browser

http://platypus.mozdev.org/index.html

Operator | Firefox Add-ons | Mozilla Corporation

Operator lets you combine pieces of information on Web sites with applications in ways that are useful. (Happy net box is a box on the net where you put things from the web that make you happy)

https://addons.mozilla.org/firefox/4106/

www.rabotat.org

Using my extension, instead, you can see the file size in the dialog box that appears just after you clicked on a PDF link and then choose to download the file or to view it as an HTML page.

http://www.rabotat.org/firefox/index2.php

TimeTracker :: Mozilla Add-ons :: Add Features to Mozilla Software

Do you spend too much time on Firefox? Do you open tabs faster than you can close them? Cannot get things done? Keep track of how much you browse with TimeTracker. I won't use this

https://addons.mozilla.org/firefox/1887/

VideoDownloader :: Mozilla Addons :: Add Features to Mozilla Software

VideoDownloader add a small icon on the status bar at the bottom of your firefox window, and a toolbar button. Just click that and download the video you are watching.

https://addons.mozilla.org/firefox/2390/