While stumbling, I came across these wonderful themes for Windows 7, just thought of sharing them with you. To install them, simply download and run to apply the themes.
An artistic theme with yellowish essence of Sun Flower. It looks great on a 30 inch display.
Want your Windows 7 to look girlish or, if Hello Kitty isn’t girlish for you, pinky. This theme is for all the cuteness of Hello Kitty.
The feeling of wonder: Taj Mahal on your desktop. This theme has customized icons to make you feel purely indulged in the uniqueness.
Gives your Windows 7 desktop inspiration of China with customized icons, this theme makes your desktop cultural.
You can have a look at more themes over here.