Gantry is a comprehensive set of building blocks to enable the rapid development and realization of a design into a flexible and powerful web platform theme. Also Gantry is available to you via the GPL license. You are free to use it in your theme development projects.
65 base widget positions
38 possible layout combinations for mainbody and sidebars
Source-ordered 4 column mainbody
Stunning Administrator interface
XML driven and with overrides for unprecedented levels of customization
Many built-in widgets and gizmos such as font-sizer, Google Analytics, to-top smooth slider, IE6 warning message, etc
Flexible parameter system with ability to set parameters via URL, Cookie, Session, Presets, etc
RocketTheme produces professional Joomla Templates, WordPress Themes, Magento Templates, and phpBB3 Styles. As well as the cutting edge designs, RocketTheme has one of the largest and most active community of web developers on the planet.