Not. I have been playing with my laptop lately. When you can't get a new machine, you start making your old machine more exciting. So I was messing around and started down this path of Windows XP Themes. Most folks have seen these before when Microsoft does them. Its nothing new. Until now -- people are putting serious effort into making some very interesting user interfaces. Two of my favorites are the Windows Longhorn theme and the Mac OS X theme. These are things you either can't have today or can't run on your PC -- until now, since we can fake it.
The Mac OS X theme is pretty fun. Its got full support for the skin, colors and appearance. They have a dock replacement and more.