function respondToClick(event) {
   //Which tag are we working with?
  var tgt = event.target || evt.srcElement;
  tagClass = tgt.id;

   //Get authors
  var allAuthors = $$('div.authorBrief');

   //Iterate and show authors only if they match the tag
  allAuthors.each(function(authDiv){
    if (authDiv.hasClassName(tagClass) || tagClass == "all") {
      authDiv.show();
      $$('#filter a').each(function(a) {
        a.removeClassName("current");
      });
      tgt.addClassName("current");
    } else {
      authDiv.hide();
    }
  });


  Event.stop(event);
}

function showIfInUse(e) {

  //Get authors
  var allAuthors = $$('div.authorBrief');
  allAuthors.each(function(author) {
    if (author.hasClassName(e.id)) {
      e.style.display = "block";
    }
  });
}