3 Column Css

I’m wishing for a 3 column css similiar to Joomlart.com.

Where you can opt to show certain modules on certain pages and if there is a page with no modules, like the forum…. then the forum will spread out the full size of the content area. So in essence, have a 3 column page with the option to make some pages 3 column some 2 column, and others 1 column and do this simply by restricting what modules show up on those pages.

Thanks!