Flat Bootstrap by XtremelySocial is a modern, fully responsive, "flat" style theme with a nice color palette, big full-width images, and full-width colored sections. It automatically adapts for desktops, tablets, and phones. It is based on the WordPress standard starter theme (_S) and the Twitter Bootstrap CSS framework. Features include a mobile navigation bar, multiple columns (grid), buttons, icons, labels, badges, tabbed content areas, collapsible content areas, progress bars, alert boxes, carousels (sliders) and much, much more. This is a theme for both users and theme developers with lots of features but without the bloat. For a live demo go to http://xtremelysocial.com/wordpress/flat/.