Creating Fullscreen Objects

Ok, so here’s the Question:
(I think a lot of people would benifit from this)

I’d like to be able to have an object, such as a basic box resize, according to the size of the browser window.

An example of this was on the easybit site of the week a few weeks ago, but i can’t find anything on how to do it. Here’s the link:

http://www.easybit.it/flash2005/main.php?language=eng

Does anyone have an idea of how to do it?