I wanted my banner advertisements to be evenly distributed between my advertisers.  I was surprised to find that there were few (if any) banner modules that would randomly select the first module, then proceed through the remainder of the modules in order as visitors reloaded pages or browsed from page to page.

I (very slightly) modified the existing MetaMod recipe for displaying modules in order, to add the facility for randomly selecting the first module in my list.

As with the original, you can insert as many, or as few modules in the array as you need.  I have seven in this example, numbered 119 through 125.

session_start();

/* set a different "instance name" for each module that you want to show only once */

$instance_name = "module_counter1";

/* use as many or as few as you like, or "0" for no module */

$modules = array(119,120,121,122,123,124,125);

if (!isset($_SESSION[$instance_name]) ||

 $_SESSION[$instance_name] == "") {

 $_SESSION[$instance_name] = rand(0,(count($modules)));

}





$index = $_SESSION[$instance_name] % count($modules);

$_SESSION[$instance_name]++;

$module_no = $modules[$index];

if ($module_no > 0) return $module_no;