title: magento: show all products below a parent node
body: <p>On a magento site, we've got one menu where we would like to always show all the products below a parent node, let's say we have got</p>
  
  <p>Root<br />
  - category 1<br />
  - category 2<br />
  ---- subcategory 2-1<br />
  ---- subcategory 2-2<br /></p>
  
  <p>When clicking on category 2, we would like to see all products assigned to category2, 2-1 and 2-2. When clicking on Root, it should show ALL the products of the store. However, when selecting category1 from within the other sections of the store, we would like to have a default behaviour.</p>
  
  <p>Normally, we would just assign a product to various categories - but as we only want this behaviour on one single section of the site, I'm not sure how to handle this.</p>
  
  <p>Any ideas?</p>
  
  <p>Thanks in advance.</p>