Blossom WordPress Theme By WordPress.org, free trial: available
Blossom is a beautiful three-column theme with rounded corners and a black, white and pink color scheme. You can change the header picture, or change the background color. There is a larger widget area above the two main sidebars where you can put a tabbed module or anything you like. The pretty pink daisy used in the large graphic is by Sourcow at Deviant Art.