Lambda is a clean, simple and lightweight Joomla template at ThemeForest. Very easy to customize and light on graphics but still well presented. The PSDs for the sprites are included and layered so that customizing is super easy. Code is valid HTML (not in the preview because of host script) and valid CSS3 .
You can choose between two styles (light and dark) and many colors, along with 3 backgrounds. Check out the screenshots to see them.
Demo | Download Lambda Joomla template