I love the hamburger menu for hiding and organizing a nav tree that has several levels. I am working on building a web app that has too many menu items, so tabs are out of question. (Of course this differs with mobile apps).
For example, http://teamfox.co/themes/pleasure/app/admin1/panels.html this theme has a gorgeous side nav and a full page search neatly tucked away non-intrusively. As a result, the user does not lose their place inside the application and can go from anywhere to anywhere else in a single click.
Best part: Additional menu items can be added without affecting the page space.