The "Shop" page of this site is a php page which displays an amazon a-store category and the second level tabs appropriate to that category, using a "node id". The html for the tabs is defined in an included page like this:

<?php


//-------------//
$tabs6= '<ul class="yui-navset bd">';
$tabs6.='<li class="first selected" id="tab6"><a href="shop.php?tab=6" >Web Development</a></li>';
$tabs6.='<li class="" id="tab180"><a href="shop.php?tab=180" >CSS</a></li>';
$tabs6.='<li class=" " id="tab183"><a href="shop.php?tab=183">Javascript</a></li>';
$tabs6.='<li class="last" id="tab181"><a href="shop.php?tab=181">DHTML</a></li>';
$tabs6.='</ul>';

$tabs180= '<ul class="yui-navset bd">';
$tabs180.='<li class="first " id="tab6"><a href="shop.php?tab=6" >Web Development</a></li>';
$tabs180.='<li class="selected" id="tab180"><a href="shop.php?tab=180" >CSS</a></li>';
$tabs180.='<li class=" " id="tab183"><a href="shop.php?tab=183">Javascript</a></li>';
$tabs183.='<li class="last" id="tab181"><a href="shop.php?tab=181">DHTML</a></li>';
$tabs180.='</ul>';

$tabs183= '<ul class="yui-navset bd">';
$tabs183.='<li class="first " id="tab6"><a href="shop.php?tab=6" >Web Development</a></li>';
$tabs183.='<li class="" id="tab180"><a href="shop.php?tab=180" >CSS</a></li>';
$tabs183.='<li class=" selected" id="tab183"><a href="shop.php?tab=183">Javascript</a></li>';
$tabs183.='<li class="last" id="tab181"><a href="shop.php?tab=181">DHTML</a></li>';
$tabs183.='</ul>';

?>

Each tab link has a parameter containing the node id:

http://thedesignspace.net/shop.php?tab=183

The value of "tab" from the query string is used to populate a variable "$tab" which is used in several places on the page. One of those spots is the line which prints out the correct bank of tabs. In this case, a new variable name is constructed by concatenating "$tab" with a string. The code that displays the correct bank of tabs is simply:

<?php 
print ${'tabs'.$tab}; 
?>