Apple made many plenty of color versions which guarantees maximum reach among their customers ranging from little kids to the older fellas. ;)
The Red version of the Nano is a special edition which is part of "(PRODUCT) RED". When people buy this version "Apple contributes a portion of the purchase to the Global Fund to fight HIV/AIDS in Africa". For info check joinred.com. The Red version is sold exclusively at the Apple Store.
There are custom made 24KT Gold Editions of the Nano 6G. If expenses are an issue in your mind this is most likely not for you. ;)
The guys at Computer Choppers are experts at turning electronics into gold! Check their site to view other Apple products in beautiful gold.
For even more options there are skins and cases available.