Glossy Stylo is a colorful theme with nice transparency effects, 2-column layout, and a widget-ready sidebar.
JustCSS is an HTML5 theme with custom colours using CSS3, based on Toolbox.
Portfolio Theme uses custom post types for portfolio pages, takes advantage of the new menu navigation, and includes a ton of neat features.
Summ is a theme in blue and white, with widgets supported, and no plugins required.
