Most useful Firefox Addons

[Spiral]

Lets start a list of your all-time most useful mozilla firefox addons for webmastering.

I'll start:

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- Display the Google PageRank, Alexa rank and Compete ranking anywhere in your browser, along with fast keyword density analyser, keyword/nofollow highlighting, backward/related links, Alexa info and more.

InFormEnter: [Only Registered users can see links . Click Here To Register...]
- InFormEnter adds a small, clickable icon next to every input field in a web form, from where you can select the item to be inserted - no typing required. You can configure it to display your frequently used information such as name, email, address... Good for website submissions to directories, etc.

What does everyone else recommend?