Tiny Menu

I discovered this cool Firefox add-on when I used Puppeee Linux.
Having more real estate on your browser is cool and Tiny Menu helps
you do that by bunching up all of the menu items in one dropdown Menu
list. This is most beneficial for netbook users where screen real
estate is precious.

After installing the add-on, you need to edit the menu. Right-click on
the Menu and choose Customize... to begin. Once in customizing mode,
drag the buttons of the Navigation bar next to the Menu dropdown.
After dragging all the necessary buttons, right-click Menu again and
uncheck Navigation bar. This will free up some pixels for your browser
to use.