In Internet Explorer (as well as Mozilla) - if you press F11 then it shows you the webpage in full screen mode. I am using it for quite a while now and i must say it let's you focus on what you are currently doing by giving a clutter free environment!
Internet and Web Tips · · · ·
Yup. I am using it too. Just want to add that you need to press F11 to exit full screen mode. The Universal ESC does not work.
@jacob sir: Yup! The almighty ESC will not work.
For more shortcuts, refer this