In order to save space on FF, I installed "Hide Menubar" extension, which hides the menubar unless ALT key is used (same as IE7). But I figured out that I use the bookmarks menu frequently, and hitting ALT everytime was an inconvenience.
So I installed "Toolbar Buttons" extension, which includes a bookmarks button that opens the bookmarks menu, right from the navigation bar. My FF looks as the attached image.

Things are great except that "LiveClick" extension does not work with that menu!! LiveClick allows me to click on a Feed, and it would open the site that feed belongs to.

Is there anyway I can customize FF just as I want?! LiveClick working, the menubar hidden, and being exactly one click away from the bookmarks menu?! I understand that my request is too specific, and this might make it hard to realize, but I hope there will be a way.

PS: I have also tried the "Compact Menu", but that was inconvenient as well.

Have you tried Personal Menu?

Try Menu Editor 1.2.6

"Menu Editor" is a good extension, but not exactly what I needed. On the other hand, "Personal Menu" worked like a charm... Thank you guys for the suggestions. Thats why we love FF, you can always count on customizing it just the way you want it to be.