ShareThis for FireFox makes sharing simple. Share anything on the web with your friends on 45+ social sites including Facebook, Twitter, Email, Digg, Reddit and more. Track top trending shares by site and automatically save content to your ShareBox.
Note from Mozilla: This add-on has been discontinued. Try MinimizeToTray Revived instead.
Minimize applications to the system tray.
Open local URLs ("file://") from any webpage. Please see the extension homepage for explanations, the mailing list and the newsgroup where I am happy to answer questions. I am sorry that - based on past experience - I had to decide to...
You can capture your screen and record your voice to make screencasts (tutorials, e-lessons, etc.).
Open IT Online allows you to open documents and images online without the need of any software to be installed. It supports Google Docs, Zoho, View Docs Online, Vuzit to edit/view documents and Snipshot, Pixlr, Sumo Paint, etc. to edit/view images.
CoLT (short for "Copy Link Text") makes it easy to copy either a link's text, or both the link text and its URL in a format you specify. This non-invasive extension simply appears as context menu items when you right-click a link. Fully customizable!
A simple extension that plays the Windows Internet Explorer start and end navigation sounds, popup blocked and information bar sounds, feed and search provider discovered sounds, and download completed sound.
Add "Go Parent Folder" menu to context menu in The Library list view and Search result in Bookmarks Sidebar.
SenSEO is an extension checking the most important on-page-SEO-criteria and calculating a grade of how good your site fulfills these criteria.
Organize your search engines with separators and folders.
FoxVox will speak any text you highlight in a web page. FoxVox can also create audiobooks in mp3, ogg, and wav formats. You can now easily turn your blogs and articles into podcasts.