Fight the text ads! Element Hiding Helper is a companion extension for Adblock Plus meant to make creating element hiding rules easier.
Xmarks is the #1 bookmarking and open tab add-on. Keep your bookmarks, and open tabs backed up and synchronized across computers and browsers. Mobile phones with Premium access. Utilize LastPass to sync passwords!
A customizable mouse gestures extension which enables to execute various commands and user scripts with six types of gestures.
IE Tab - an extension from Taiwan, features: Embedding Internet Explorer in tabs of Mozilla/Firefox...
UnMHT allows you to view MHT (MHTML) web archive format files, and save complete web pages, including text and graphics, into a single MHT file in Firefox/SeaMonkey.
Defragments your Firefox "Places" database (history/bookmarks)
This greatly reduces the lag while typing in the address bar and the start-up time.
This extension features configurable automatic cleaning, periodic reminder, and internationalization.
Extension to clean and vacuum your firefox places database.
Add useful extra features to Gmail, like hierarchical labels, an unread message icon on your browser tab, file attachment icons, and more.
Supports to hide Menu Bar automatically, you can press the ALT key to show it temporarily.
Add useful extra features to Google Reader, like feed favicons, inline article previews, and unread counts in your browser tab with Better GReader.
An extension to hide the caption of Firefox, displays Minimize, Maximize/Restore and Close buttons on the menubar/nav-bar, and includes "Tiny Menu" function. This extension also provides "Bookmarks" and "Histroys" buttons with popup menu.