Karma Blocker 0.4

Use a "karma" scoring mechanism like that in SpamAssassin to block nuisances on the web.
An extremely powerful, yet lightweight, alternative to extensions like AdBlock Plus.

Especially useful for blocking third-party resources to help combat privacy leaks (cookies) and security problems (XSS). Karma Blocker is intended for the advanced user. It is highly recommended to read the documentation (at the "homepage" link below.)

It uses a simplistic definition language to assign "karma" points to every resource that Firefox loads when rendering pages. If any resource gathers enough points, it is blocked

Operation: Every time Firefox begins to load any resource (page, image, style sheet, javascript file, etc.) Karma Blocker will first check it against the rules it is configured to use. If the rules match that request, it will be denied and never load. There are certain exceptions:

• When Karma Blocker is disabled (and the status bar icon is greyed out), all requests will be allowed.
• When the resource is not from one of the schemes http, https, ftp, chrome, all requests will be allowed.
• Three different checks are made to ensure that resources that form part of the browser itself (i.e. the back/forward buttons, icons, etc.) are never blocked. 

Major Features:

1. Request-time blocking of any resource. (Blocked objects never load, never use bandwidth, never set cookies.)
2. Karma (or score) based weighting of objects, similar to popular spam filtering solutions like SpamAssasin.
3. A flexible expression language for powerful filtering, on a richer set of data than simply "the URL".
4. Global function injection; if a script is blocked, yet functions in it are still called, injecting a blank function of the same name will eliminate any errors.

Enhancements:

• Mark Firefox compatibility with 3.0 through 3.5.
• Add option for the monitor window to gather only blocked resources.
• Add configuration setting to enable/disable the element collapsing feature (now off by default), and make it less aggressive when it is enabled
• Allow functions with properties to be injected, i.e. `inject=_gat._getTracker` will eat undefined function errors from blocked Google Analytics scripts.
• Disable wrapping when editing rules, so long lines display on one line (with a horizontal scroll bar).
• Never block core parts of the browser itself.
• In the monitor window, you can copy data, remove items, open URLs, and expand/collapse rows via a context menu.
• New default rules which are highly functional.

Requirements: Mozilla Firefox