Fancy getting that next generation, Longhorn look on your Windows XP desktop? Can't wait for the real thing to be released? You need the Longhorn transformation pack.
What this software will do is give you the latest look of Longhorn on your Windows XP and Windows 2003 server. All you need to get this is to download a 13MB zip file and install. According to the website, "you can rollback your system files to obtain new updates from Windows Update and reinstall it so you don't need to use Batchmod or wait for the author to make new updates". Many GUI components can be made to look "Longhorn", including the login dialogues, start button, progress dialog and toolbar button. As with all these kind of modifications, install at your own risk.