Adblock Filterset.G Updater
Asblock Plus - blocks annoying ads and allows you to customize.
Batch Download - downloads following a set of rules.
Colorful Tabs
Copy Plain Text - useful when you don't want to copy more than text
Download Sort - downloads and renames files
DownThemAll - selects files to download later, renames
Fasterfox
Forcastfox - shows weather information for your current location
ImageZoom
ImgLikeOpera - allows a person to only show cached images, saves bandwidth
NoTabCloseButton
Noscript - stop all javascript, javascript it enabled based on a whitelist of sites which may run javascripts. blocks ads and junk
PDF Download - makes google turn a PDF in to a html for you
Ressurect Pages - opens dead pages with google cache
ScrapBook - saves sites locally on your disk, in an easily browseable way
SessionSaver <-- need to edit the version number. opens tabs as you left it before before quiting.
StumbleUpon - community of people with same interest index sites they liked, you click and get taken to a specific topic
Unplug - shows direct links to download media from youtube and such where media links are hidden away
CoolIris seems like it downloads webpages before clicking, eats bandwidth?
Fasterfox and StumbleUpon also does it, but has settings to moderate it.
Fasterfox makes rendering and download performance go up
StumbleUpon takes you to a random website in a preset category.