Final stable version of menux came out 0.2.4. Works in Firefox 1.0 and 1.5.
MenuX was designed for laptop use where maximum screen realestate is desired. Adds the ability to collapse any toolbar.
Available in: EN, FR, IT, DE, PL translations.
A more current version 0.2.4.1 can be found on my website. This version was tweaked to work with StumbleUpon, tabbrowser prefs, session saver, yahoo toolbar, webdeveloper toolbar.