The new dotnetnuke 5 skin has lots of new features that can make you owe. The most of the features you can see on the default Extropy skin provided within the dnn itself.

The most appreciated feature is its totally div based rather than table based.  Another exiting feature is SkinWidget is used, user can choose the options like Color, Text size, Layout on which user is intrested.

The below screen shows that you can put the options so that end users can select the preferable option.

The left portion (Text size option), Middle Option(Color option), Right portion(Width Option).

Text size option and Width option are provided on the default Extropy skin . Another one i created my self to test the Skin Widget feature. I just created css to change the background color of the site. But more css can be added to change the color of the entire elements used on the site.