"WebDesignFan is a design related blog about web design, photoshop, freebies and tutorials. We publish useful information dedicated to web designers and developers. Here you can find free resources like vectors, wordpress themes and a lot of inspiration. "
Just key in the URL of any website built with a responsive template and Responsivator will load it up in a series of iframes that are set in different sizes. Aside from desktop sizes, other default screen sizes include mobile devices such as the iPhone, iPad and the Nexus 7.