Well, at least not without some hacks. There is no way to make a box 100% of the height of the screen with a single CSS command like "height: 100%". Though I wish it was that easy.

You will have to do a google search to find some of the ways others have accomplished this feat. Some use negative margins like "margin-bottom: -9999px;" and others just place a div around the content and the right/left side bar and set the background of that div to some image to make it LOOK like the side bar goes to the floor.

But like I said, you will have to get some half-browser-working CSS hack to do the trick.