A couple screens of the prototype versions of the responsive "List View" layout (for pages set to use "List View"). Final look will most likely change as I am constantly making tweaks to it (and of course you will be able to tweak it fairly easy yourself).
This first shot is what it looks like after the sidebar drops to the bottom of the list
This next shot happens at the next responsive break point (medium max)
This last shot is of the smallest break point (max width narrow).