title: Select a Random Product for every 20 products in a collection
body: <p>Here is My Code,</p>
  
  <pre><code>$collection = Mage::getModel('catalog/product')
              -&gt;getCollection()
              -&gt;setStoreId($storeId)
              -&gt;addStoreFilter($storeId)
              -&gt;addAttributeToFilter('status', 1)
              -&gt;addAttributeToFilter('visibility', 4)
              -&gt;addCategoryFilter(Mage::getModel('catalog/category')-&gt;load(500))
              -&gt;addAttributeToSort('created_at', 'desc');
  $collection-&gt;getSelect()-&gt;order(new Zend_Db_Expr('RAND()'));
  $collection-&gt;setPageSize(20);
  </code></pre>
  
  <p>Because of this i'm getting Random 20 Products but i want it should give One Product from 1st 20 products, One Product from 2nd 20 products... 20products.</p>
  
  <p>How do i make this ?</p>
  
  <p>Any Ideas ?</p>