Extreme Drupal CSS aggregation

gistfile1.aw

<?php

/**
 * Implements hook_css_alter().
 * Force every CSS file on every_page in the same group, in order to have only one aggregated file, and reduce http requests.
 */
function YOURTHEME_css_alter(&$css) {
  foreach($css as $file => $info) {
  if ($info['type'] == 'file') {

    // Mode system CSS to theme. Set a negative weight so they are loaded first.
    if ($info['group'] == CSS_SYSTEM) {
      $css[$file]['weight'] = -0.01;
      $css[$file]['group'] = CSS_THEME;
      $css[$file]['every_page'] = TRUE;
    }

    // Remove module default CSS, exept admin_menu.
    if ($info['group'] == CSS_DEFAULT) {
      if (strpos($file, 'admin_menu')) {
        $css[$file]['group'] = CSS_THEME;
        $css[$file]['every_page'] = TRUE;
      }
      else {
        unset($css[$file]);
      }
    }

    // Alter our theme CSS. Load them on every page, after every other CSS
    if ($info['group'] == CSS_THEME) {
      $css[$file]['every_page'] = TRUE;
      $css[$file]['weight'] += 0.1;
    }
  }
  }
}