For this year's ZURBwired we're not content to just build an awesome desktop site - we're going to build a mobile site in tandem, using a front-end framework we've been developing called Foundation. We just finished building the static prototype (layout for all pages), so that next we can bring in the copy and then the visual style.
With the pages complete on the desktop we'll then work through the mobile component. Foundation takes care of a lot of the mobile layout, but by doing interactive reviews of the screens on different devices (iPhone, Android phone, iPad, etc) we can adjust the layout and style to suit these views.
You can check out the prototype on our extranet (the mobile, responsive view is still a work in progress):