Like the Composite module, Panels can be used to create a page that looks like it has sidebars but in actuality it is the Panels module that is doing all the work.
Panels has the same layouts Composite as well as the option to create your own layouts. The screen shot below shows an example of an alternative three column layout that you can use for a page. This is Panels' flexible layout feature. It allows you to create the page layout you need.