Operator leverages microformats and other semantic data that are already available on many web pages to provide new ways to interact with web services.
Legacy version (get latest on outwit.com). Browse though images online with just a few clicks: View collect images from the Web effortlessly. Scroll through high-res photos, drag them into your basket, view slideshows & save directly to your disk.
Note from Mozilla: This add-on has been discontinued. Try one of these instead.
Get rid of all toolbars in fullscreen for kiosk applications.
Paste URL or text to any tabs or a new tab and load it immediately, like 'Paste & Go' feature, but unlike 'Paste & Go', this extension will paste text from clipboard to a tab without focusing on the tab first.
Like homestarrunner.com? Notice how small the cartoon is? Fix it with this extension!
Turns Idle FireFox into a ScreenSaver and Photo Viewer! Nice non-offensive pictures updated daily! Or your own pictures. FullScreen. Works great on Linux or dual monitors! Resouce Efficient! Support Media RSS. Recommend your own favorite pictures!
Collector's Note don't work often for me
Note from Mozilla: This add-on has been discontinued. Try Evernote instead.
Clipmarks lets you clip and share specific parts of articles, or anything else you read.
Tab grouping, vertical tab tree, multi-rows, and various tweaks for power users.
Jetpack Prototype is an experiment in making it easy to build Firefox add-ons using common web technologies.