// old school image src replacement
       var stories_g = new Image();
       stories_g.src = "http://images.salon.com/img/cover/top_stories_g.gif";
       var stories_r = new Image();
       stories_r.src = "http://images.salon.com/img/cover/top_stories_r.gif";
       var active_letters_g = new Image();
       active_letters_g.src = "http://images.salon.com/img/cover/active_letters_g.gif";
       var active_letters_r = new Image();
       active_letters_r.src = "http://images.salon.com/img/cover/active_letters_r.gif";

       function toggleMostPopular(content) {
             if (!document.getElementById) return false;

             if (content == "stories") {
                   document.getElementById("most_popular_stories").style.display = "block";
                   document.getElementById("most_popular_letters").style.display = "none";
                   document.getElementById("most_popular_stories_tab").src = stories_r.src;
                   document.getElementById("most_popular_letters_tab").src = active_letters_g.src;
             }
             else if (content == "letters") {
                   document.getElementById("most_popular_stories").style.display = "none";
                   document.getElementById("most_popular_letters").style.display = "block";
                   document.getElementById("most_popular_stories_tab").src = stories_g.src;
                   document.getElementById("most_popular_letters_tab").src = active_letters_r.src;
             }
             return false;
       }