Make your bookmarks bar better. Roomy Bookmarks Toolbar can: hide bookmarks/folders name(dock like), multirow, autohide and many another features(more than 20).
Customize your bookmarks bar using one add-on.
Scans for bookmark duplicates and allows you to delete them
Facilitates opening multiple tabs from the Bookmarks Menu and various other bookmark/history related dropdown menus. Less need to keep reopening menu, without using the sidebar. Optional auto-closing feature adds extra convenience.
Bookmark Sorter helps you sort your bookmarks. You can define rules to match against bookmark titles and URLs, and Bookmark Sorter uses these rules to move your bookmarks to the appropriate bookmark folders.
This add-on allows you to open Bookmarks as HTTP's POST Requests. Usefull if for example you want to bookmark search engine's results
Remove icons from Bookmarks Toolbar.
Note! Does not work with Firefox 20 and up! Please see http://antennasoft.net/robcee/2012/04/20/bookmarks-deiconizer-userchrome-edition/
This addon enhances all the tooltips in Firefox. DOWNLOAD the new Firefox 4.0-compatible version there: https://addons.mozilla.org/firefox/addon/7314/contribute/roadblock/?src=version-history&version=3.0.20110409 :)