I am trying to replicate the ebay filtering system: antiques.shop.ebay.com/items/Antiques__W0QQ_sacatZ20081

as you can see the items on that page are being pulled in from the sub (sub/sub) categories of the main category (Antiques)

how can i pull off the above so that a category can display items from its sub categories and show them.

the solution needs to mysql/php driven.