Celadon, was designed and released by Themes Boutique, is a free theme for WordPress that focuses on great looks and usability. Celadon is completely free licensed under General Public License, comes with a custom control panel and there are also 6 color scheme themes to pick from. Here are the main features of Celadon:

• Celadon comes with 6 color variations out of the box so you can personalize your blog with your favorite color. The colors are: green, blue, purple, red, orange and black;
• Features it’s own custom settings panel under the Appearance section allowing you to set things as well as customize the navigation bar;
• Widgetized sidebar is ready;
• All of the comments will use Gravatar user pictures by default.
• http://www.themesboutique.com/theme/celadon