Firefox - Extensions and tweekin'
Adblock Plus
"Ever been annoyed by all those ads and banners on the internet that often take longer to
download than everything else on the page? Install Adblock Plus now and get rid of them."
Download Here


Adblock Filterset.G Updater 0.3.1.3
"This is a companion extension to Adblock or Adblock Plus and should be used in conjunction
with it. This extension automatically downloads the latest version of Filterset.G every 4-7 days."
Download Here


Bugmenot
"Bypass compulsory web registration with the context menu via www.bugmenot.com."
Download Here


DOM Inspector
"DOM Inspector is a tool that can be used to inspect and edit the live DOM of any web document or
XUL application. The DOM hierarchy can be navigated using a two-paned window that allows for a 
variety of different views on the document and all nodes within."
Download Herer


Firebug
"Firebug integrates with Firefox to put a wealth of development tools at your fingertips while
you browse. You can edit, debug, and monitor CSS, HTML, and JavaScript live in any web page."
Download Here


Flashblock
"Never be annoyed by a Flash animation again! Blocks Flash so it won't get in your way,
but if you want to see it, just click on."
Download Here


Tab Mix Plus
"Tab Mix Plus enhances Firefox's tab browsing capabilities. It includes such features as
duplicating tabs, controlling tab focus, tab clicking options, undo closed tabs and windows,
plus much more. It also includes a full-featured session manager."
Download Here


Web Developer
"Adds a menu and a toolbar with various web developer tools."
Download Here