Comments: setFlash
2 - Don't forget the redirect
Use setFlash to mimic the Rails way of showing a flash message. That is, the form is submitted and the user is transferred back to the listings page for the model saved with a flash message. On successful save, use $this->Session->setFlash("your message") and don't forget to send the user to the listings page $this->redirect("/listing");

By Finster on 24/10/08
1 - Using a custom layout
It's not clear in this documentation, but to use a custom layout, you can create a flash_message.ctp and pass "flash_message" as the layout.
Then, the layout should contain something like:
<div id="flashMessage" class="message"><? echo $content_for_layout ?></div>
Now, the really cool part is that anything you passed in the $params array gets set to a viewVars in the flash layout. So, I could have the following if I passed 'class'=>'agony' to the setFlash() call:
<div id="flashMessage" class="<? ife(isset($class), $class, "flash") ?>"><? echo $content_for_layout ?></div>