I recently had a friend who wanted to find out his windows product key. his sticker had worn off his computer and he needed to reinstall Windows. There is a great tool for this called the Magical Jellybean Keyfinder. I have been using it for years and it has just been a great tool. It will not only find wour Operating System product key but it will also find the keys for all Windows based products such as Office, Visio and Project. Its a simple tool to get and use but it is a real blessing in many IT situations.