End of out of stock message
If a product is temporarly out of stock, it would nice for the user to have an option to be alerted when the item is available again.
From the given product page, he would just have to click on a button "alert me when available" and to give his email address (or to sign in if he already has an account).
When the product is back for sale, an email would be automagically sent to him.
I like the "typo": automagically :-)