Hello,
I'd appreciate if anyone knows or have any free scripts or script pointers that can produce the effect like http://www.overstock.com, which allows multiple departments each of which has different theme or contents... Customers once selected one department, he/she will stay with it throughout all the pages underneath this department, unless a different department tab is pressed.

I am developing an online store that will have at least two departments that carry difference types of products.

Much thanks in advance.
Jason