Imagine you are here:
http://demostore.x-cart.com/toys/rc-toys
We want to see
Cube Goodies, RC Toys, Science Toys as icons above the products. Also if the three categories had more subcats then the same three icons would show. It's a quick way to navigate where you are without having to jump to the Toys main category.
I've worked out how to do this and some other tricks with the navigation so I wouldn't worry about it too much.