Site alert module provides functionality to display urgent message to all users. Originally was created for the Site alert module with a lot of Ajax when user can stay on the same page for significant period. This is a simple tool which uses periodic polling from client side within small dedicated iframe. Pulled file sitewide_msg.poller.php using limited Drupal bootstrap to decrease performance overhead. Usage ----- Install module according to standard Drupal procedure and enable it. After that you'll be able to configure displaying sitewide messages in two way: - by assigning dedicated block to desired region; - by using in your page.tpl.php new variable $sitewide_msg, sample usage from real project:

  if ($sitewide_msg) {
    echo $sitewide_msg['placeholder'];
  }
  else {
    // optional - to keep spacing when module disabled.
    echo " "; 
  }

To send message, as well as to configure polling interval and optional expiration of the displayed message, use screen at admin/config/people/sitewide_msg . Have fun!