diff --git includes/module.inc includes/module.inc
index 59f546c..960d5cb 100644
--- includes/module.inc
+++ includes/module.inc
@@ -121,11 +121,40 @@ function drupal_build_system_lists() {
         drupal_get_filename($record->type, $record->name, $record->filename);
       }
     }
+    drupal_build_system_lists_overrides($lists);
   }
-
+  
   return $lists;
 }
 
+/*
+ * Add or remove to the enabled modules/themes as specified in the
+ * $conf['system_lists_overrides'] variable in settings.php.
+ *
+ * @param $lists
+ *  An array keyed by system record type (modules, themes, bootstrap).
+ */  
+function drupal_build_system_lists_overrides(&$lists) {
+  if ($overrides = variable_get('system_lists_overrides', array())) {
+    foreach ($overrides as $type => $items) {
+      foreach ($items as $name => $status) {
+        if ($status) {
+          if ($type == 'modules') {
+            $lists[$type][$name] = $name;
+          }
+          else {
+            $theme = db_query('SELECT * FROM {system} WHERE name = :name AND type = :name', array(':name' => $name, ':type' => $type))->fetchAll();
+            $lists[$type][$name] = $theme;
+          }
+        }
+        else {
+          unset($lists[$type][$name]);
+        }
+      }
+    }
+  }
+}
+
 /**
  * Find dependencies any level deep and fill in required by information too.
  *
diff --git sites/default/default.settings.php sites/default/default.settings.php
index bc97373..67c32b5 100644
--- sites/default/default.settings.php
+++ sites/default/default.settings.php
@@ -359,3 +359,26 @@ $conf = array(
  * Remove the leading hash signs to disable.
  */
 # $conf['allow_authorize_operations'] = FALSE;
+
+/**
+ * Dynamically enable/disable modules and themes.
+ *
+ * Override choices made on the Modules page using the array below. Note that
+ * general enable/disable should still happen on using the admin web pages. For
+ * example, enabling a module here does not run its hook_install().
+ *
+ * Remove the leading hash signs to enable.
+ */
+ #$conf['system_lists_overrides'] = array(
+ #  'themes' => array(
+ #    'seven' => 0,
+ #  ),
+ #  'modules' => array(
+ #    'devel' => 0,
+ #  ),
+ #  'bootstrap' => array(
+ #    // Add modules which should be (not) loaded during bootstrap. Modules here 
+ #    // should also be listed in the 'modules' section above.
+ #    'devel' => 0,
+ #  ),
+ #);
\ No newline at end of file