Using Hidden Regions
In addition to the right-hand column, most of our pages have empty regions that can be filled with custom content. Click on the Configurations sub-tab of any page to find "LEFT-COLUMN-BLOCK" and "DEFAULT-EXTRA." Here is where these two regions fit in the page layout that is defined in the templates.
What does this mean?
You can place custom xhtml blocks or custom index block/format pairs in these regions to spruce things up! See Adding a List to the Bottom of a Page and Add/Remove Left Column Item.
Note: Sorry, all standard "listing pages" already use the DEFAULT-EXTRA region.