Here are a few Firefox 
add-ons you may want to investigate & use.WeatherBug 2.0.0.4
Display your local weather conditions....Current, high & low temperature, sunny or rain for three day without downloading by just passing over it with your mouse. Or, you can get live, local weather conditions and forecasts, radar, and severe weather alerts from WeatherBug's community of neighborhood weather...
https://addons.mozilla.org/en-US/firefox/addon/weatherbug/
Add-on Compatibility Reporter ...
Help Mozilla make sure your favorite add-ons get updated for upcoming Firefox releases by using this extension to report whether they still work or are having some issues with alpha and beta releases.
https://addons.mozilla.org/en-US/firefox/addon/add-on-compatibility-reporter/
ColorfulTabs 4.6.5
The most beautiful yet the simplest add-on that makes a strong colorful appeal. Colors every tab in a different color and makes them easy to distinguish while beautifying the overall appearance of the interface.
https://addons.mozilla.org/en-US/firefox/addon/colorfultabs/
Download Manager Tweak 0.9.5
Allows the download manager to also open in a tab or sidebar, and adds some optional display changes.
https://addons.mozilla.org/en-US/firefox/addon/download-manager-tweak/
Open in IE 1.3
This add-on enables you to open a link or the current page in a new Internet Explorer window. No more copying and pasting links for those sites that refuse to function correctly in Firefox!
https://addons.mozilla.org/en-US/firefox/addon/open-in-ie/
Print Edit 3.5
Allows editing of the web page content while in Print Preview mode. Editing the web page prior to printing can compact the layout and remove unwanted content such as adverts, sidebars and blank pages. Any element can be formatted, hidden or deleted.
https://addons.mozilla.org/en-US/firefox/addon/print-edit/
ReminderFox 1.9.9.3
ReminderFox displays and manages lists of reminders and ToDo's. ReminderFox makes sure you remember all of your important dates via easy-to-use lists, alerts, and alarms, right in your browser without the need for a separate calendar program.
https://addons.mozilla.org/en-US/firefox/addon/reminderfox/
Text to Voice 1.05
'Text to Voice' or 'Text to Speech' is one of the coolest add-ons. It gives Firefox the power of speech. Select text, click the button on the bottom right and this add-on speaks the selected text for you. Isn't it brilliant? Audio is downloadable.
https://addons.mozilla.org/en-US/firefox/addon/text-to-voice/
Toolbar Buttons 1.0
Toolbar Buttons is the single biggest button pack for Firefox (over 100 buttons), Thunderbird (over 75 buttons) or Sunbird (over 25 buttons) there is. You will find buttons that enable hidden functionality or is too many clicks away, but some of the best buttons are those unique to the extension, a number that is ever increasing.
https://addons.mozilla.org/en-US/firefox/addon/toolbar-buttons/
WebMail Notifier 2.7.5
Notifier for gmail, yahoo, hotmail, aol and more webmails.
WebMail Notifier checks your webmail accounts and notifies the number of unread emails...
Supports : gmail, yahoo, hotmail, aol, daum, naver, nate, paran, POP3/IMAP and more!
https://addons.mozilla.org/en-US/firefox/addon/webmail-notifier/
Meet The Smilies 2.0
This Addon will actually allow you to be able to insert smilies & emotion-cons anywhere on the web, forums and especially on FaceBook !
https://addons.mozilla.org/en-us/firefox/addon/meet-the-smilies/
Greasemonkey 0.9.1
https://addons.mozilla.org/en-US/firefox/addon/greasemonkey/
Customize the way a web page displays or behaves, by using small bits of JavaScript.......
A more in depth explanation of Greasemonkey.........
is an excellent addon which makes Firefox a lot better. Unlike many other addons that let you do one particular thing, possibilities with this one are incredible. Greasemonkey extension lets you add so called ‘user scripts‘ which can add more functionalities or change the behavior of a web page. These scripts let you control any aspect of a web page’s design or interaction. For instance, you can add video download functionality to video sharing site like youtube, OR disable all ads on myspace OR change the appearance of gmail and lots lots more…
So, how does it work?
* 1. Install Firefox, if you haven’t done it already.
* 2. Install Greasemonkey. Once done you should see a small monkey face at the right bottom corner of your browser window.
* 3. Start adding ‘user scripts.’
Userscripts.org is a directory currently listing over 2.000.000 Greasemonkey ‘user scripts’. All of these scripts are developed by users themselves. Most of them directed to solve common web problems, i.e. removing annoying ads, adding additional navigation options, and changing the look of the page. Once you’re on userscripts.org you can use their tag cloud box to quickly locate desired scripts. For instace, clicking on ‘myspace’ tag will show get you all scripts designed for myspace.
Some of the popular script categories are:
* Myspace (ex: remove all ads from Myspace, remove all flash media from profile pages, …)
* Facebook (change the look of Facebook, remove ads, automatic page refresh every 30-90s, …)
* eBay (add new column displaying total item cost (price+shipping), auto-feedback, …)
* Amazon (disable ads, show prices in different currencies, for each product show prices from other sellers, …)
* Gmail (change appearance, integrate google reader into gmail, ….)
* Youtube, GoogleVideo (ADD video download option, change site theme, … )
* and many more including Flickr, Del.icio.us and whatever is popular.
Installing user scripts is extremely easy, just click on the script’s install button and Greasemonkey will do the rest. In case you don’t see desired changes then try restarting the Firefox.
Tips:
*Try to avoid installing scripts from elsewhere but userscripts.org.
*While browsing through scripts you may see something like ‘NOTE: manual configuration required‘, if you have no idea how to configure them just avoid them.
http://www.makeuseof.com/tag/greasemonkey-firefox-addon/
Below is a screen shot of my computer with the above listed add-ons shown on top & bottom of page!
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