UIkit by Yootheme is a stand alone web framework, which allows you to build lightweight and well-structured websites by the help of modern script technologies and a compilation of powerful components, which are combinable with each other. Yootheme provide this free framework on GitHub. The integrated customizer helps you to create beautiful template styles with few clicks. Great CSS skills are not necessary for that. UIKit use also LESS, which is good for the website speed. You can use this framework, like Bootstrap, platform-independent under MIT License.
Odio is free minimal OpenCart theme, which comes in 6 pre-defined light colors. You can use it best for fashion stores. The SEO optimized grid works in all popular browsers, is also responsive for any device. Kulerthemes realized it for OpenCart 1.5.4+ by the use of Google fonts for the typography. You can get it in a commercial version with 5 helpful OpenCart modules. The free theme version is available on developers website.
Shoe Store is BSEtec first shoe store theme for Magento. Its ready from Magento versions 1.4+. Shoe Store based on CSS3 and HTML5, use the Google Font directory for all fonts. Its grid based on Bootstrap, is thereby ready for any device and resolution. Fine user friendly features are the integrated back to top button or the product zoom function. The download is free. Shoe Store is available on developers website or on Magento Connect.