Awesome plugin!

A Windows search program turned Firefox Extension, GSI Creates Site Maps based on Google queries. Useful for both Penetration Testing and Search Engine Optimization. GSI sends zero packets to the host making putting your activities into anonymous stealth mode.

This tool employs some of Google's Advanced Operators (Site and Inurl).

By sending a site query such as, site:ask-samknoll.com, to Google, one can retrieve all files Google has indexed. However, Google only retrieves a maximum of a thousand results. In order to get more results, one can combine the advanced operators, such as site:ask-samknoll.com inurl:cp. GSI does both of these in order to generate a site index.

By default the plugin only displays an indented site index with only the directory name showing for each link. You also have the option of having it show the entire link.

This extension creates an on-the-fly Google Custom Search Engine, based on the links from the current page you're on.  It adds a new toolbar to the bottom of your browser window with one great feature… when you aren't using it all you see is a small button.  Click it to open the toolbar

There are a variety of options to choose from when doing your searching
* SiteSearch: If checked, a simple site search will be performed with the provided query, using the regular Google site: operator.

* URL Extraction
Exact: use extracted URLs without modification, to create a very "narrow" search engine.
Paths: use the host+path from an extracted url, but omit any filenames.
Hosts: use only the host from extracted urls to create a "broad" search engine.

* Extraction modifiers
Filter: some of the extracted URLs might be dominate search results for almost any query. For example, if we extract http://nih.gov, it is unlikely any other extracted URL will appear in search results. By enabling this option, the search engine will avoid certain overly-dominant URL patterns, like nih.gov/*.

Boost exact: this allows combination of host or path URL extraction, with an extra layer of exact URL extraction. Exact urls will be prefered in the search results.

* Other options
New Tab: open search results in a new tab.

This small Firefox extension just adds button to your browser for easy access to current opened site's whois source.  It inserts a small unobtrusive button next to your address bar.

This is produced by domaintools.com

This nifty little extension checks the current page you are on to see if Google Analytics is installed. It'll automatically detect the presence of the tracking code and report back to your browser's status bar.

No, this doesn't mine any of the data but it does shed some insight into the level of sophistication of your competitor's online efforts.

This plugin gives you the ability to view a site's server software, IP address, location flag, and provides quick links to Whois and other domain information.  Access is from a single, little button placed on your status bar.  There are other plugins that provide the same information but this is a nice unobtrusive choice that does exactly what it says.

Ever run into a 404 Error instead of the page you wanted to see on a competitor's site?

This add-on solves that in most instances.

Very nifty and useful tool that gives you the ability to see pages that may have been moved/removed.

404-page is not found?  Now it will be!

Allows competitive intelligence agents the ability to perform "packetless" discovery of target resources utilizing publicly available information.

Simply visit the target entity's website, right mouse-click and navigate to the PassiveRecon menu or use the new status bar menu. From there you can open individual "public domain" websites or Show All sites at once.

Lets you open a specific link without sending the HTTP referer information.

Private Browsing.

Once turned on this extension monitors FireFox for its activities.

Once turned off Distrust removes history items cache and cookies that were used during the distrust session.  Cookies are expired and removed when you end your firefox session.

Not an extremely full-featured tool but it does do what it is supposed to.  I like the use of the word "Spy" n the name as well.

Shows HTTP headers on statusbar.

Features:

• Up to 5 statusbar panels
• Request and response headers
• Custom headers
• Tooltip headers
• Menu with headers for statusbar panels