Full screen

Getting the entire movie clip to expand to the viewable size is easy but I was wondering if anyone could shed some light on having certain elements on the stage move to the edges of the screen. What I mean is how do you make it so you have content that will remain in one place no matter what size the resolution and have others move to fill the available empty space? like this: http://www.thanea.com/ars/ It’s the one thing on that site I’m not sure how to do but im sure it’s something fairly simple and im going to kick myself once someone shows me a method. :puzzled: