categories side box?

Hi all I’m looking for the Categories side box mod like Magento has that refines the category. This is a demo link for what I am looking for http://demo.magentocommerce.com/bed-and-bath. When u click on the main category on the top option bar all the sub-categories show on the left side when the page opens. For example on that link click on furniture, and then on the left side there are options of Price, color and subcategory. How do I add this refine search feature?

Wow, how arrogant is that? Their main category dropdown nav in the header requires javascript to function, and they put a big warning banner at the top of the screen "this website requires javascript to function". But the dropdown does nothing, not even slick operation, that a CSS dropdown can't do. They just don't want anyone to be able to shop without js. It does appear that there are alternate paths to get to products.

Meanwhile, there is not a built-in menu function like that; however, you can install and configure Categories Dressing to work similarly. It could even be customized fairly easily to get some of the level-aware behavior, but there is a lot of involved custom coding in that menu's fancy functions that would take a bunch of work to replicate.