RockinDark1 is a widgetized, three column theme that features a dark grey background, black sidebars, and a beautiful grey/blue/green color scheme.
The Green One is a compact and lean theme for WordPress with a bit of Web-2.0 stylishness. It uses JQuery to keep the index and archives compact.
Simplus is a single column, simple theme for WordPress.
Flat is a rounded, light green, two column, widget ready theme for WordPress.
Platinum is a modern, 2-column Widget-ready theme created for WordPress.