gistfile1.js

disp_date = function(obj) {
  if(obj <= 0) return;

  var date        = new Date()
    , tillNextDay = (24 - date.getHours()) * 3600000
    , waitLoop
    , dateLoop;

  obj.html(current_date());
  waitLoop = setTimeout(function() {
    clearTimeout(waitLoop);
    obj.html(current_date());
    dateLoop = setInterval(function() {
      obj.html(current_date());
    }, 86400000);
  }, tillNextDay);
};