Firefox extensions (in Off-topic)

Having to re-install a lot of applications and programs to my desktop pc after my recent fun and games gives me the opportunity to start out from a clean slate.
Firefox was one of the first things I put back on along with the greasemonkey extension and Verifex's CB script.

There's a hatful of other extensions that I'll put on but just to help me wheedle out the wheat from the chaff please tell me what your favourite FF extensions are, and why ?

ForecastFox

It's a nice reminder that there is a real world outside the haunting glow of your computer screen.

I like the following (and quite a few more)

In general
Tab Mix Plus
Adblock
del.icio.us integration
Foxylicious
Forcast fox
Flash Block

Also
Web developer toolbar
HTML validator (via Tidy)

As for why. They each make my life easier :-)

I like the following (and quite a few more)
Tab Mix Plus: Allows much better control of tabbed browsing
Adblock: Filters out ads that I don't like
del.icio.us integration: I keep my booknarks in del.icio.us
Foxylicious: Auto update my bookmarks on each computer I use
Forcast fox: Weather forecasts (I turn off the stupid alert slider though)
Flash Block: Only play flash when I say you can play flash

Also Web developer toolbar: good, basic tool for web developement HTML validator (via Tidy): fast way to find errors in pages

I use these:

SearchStatus - Check Google Pagerank and Alexa Page Rank of current page.
Fasterfox - Time how long it takes to load pages, and speed up FF a little.
DownThemAll! - Lets you download every piece of content from a page (e.g. images, sounds) with a integrated download manager.
IE Tab - Lets you use an instance of IE inside of firefox. Is it creepy, yes!
Mouse Gestures - Control the browser with the right mouse button and your mouse movements.
GreaseMonkey - I think most of you know what this one is, but it lets you make userscripts to control pages. - MY FAVORITE! :)
Web Developer - Great for controlling pages that don't like to be controlled, and web development.
Colorful Tabs - Makes using FF very cool with different colored tabs for everyone!
Console2 - A much better JS console for firefox.
LiveHTTPHeaders - Lets you watch http headers in real time, great for developers.
Amazing Media Browser - Embedded Social Media Sharing, great slim client, fun to play with. (Also manages all media on current page
Tamper Data - Lets you view and modify HTTP/HTTPS headers, great for developers.
Hope you like it.

oh I forgot

RefControl - Control what gets sent in http referrer on a per-site basis.

Adblock - obvious, no ads :)

Adblock Filterset.G Updater - automatically cares about your AdBlock Filterset. Since i have this, i never had to adblock sth. manually, and even better, i never had to DeAdblock anything manually too :)

NoScript - blocks all Javascript, but can be enabled via single click on status-bar-icon on site-by-site basis.

Status-bar Calculator - adds a very simple calculator to your status-bar. very nice to calc loans, AC-effectiveness or whatever within cb :)

CustomizeGoogle - removes adds from Google, links to whatever other search-engines you like, .. just enhances google's results. Can also block Google Analytics :)

Morse - learning how to morse while you play CB.

I guess that's it what i am using, have fun playing around with those !

I like the Tab Mix Plus and Colourful Tabs extensions. Looks like my daughter is gonna love the Calculator one too.
One that I quite like that's not been mentioned so far is ReminderFox. A little calendar/organisor that just sits at the bottom of FF out of the way until it's time to remember you about that appointment. It's like the calculator extension, there's obviously better apps out there but it's nice to have it built in to FF.