jQuery.fn.observe = function(time) {
  return this.each(function() {
    var field = $(this);
    var change = false;

    field.live("change", function() {change = true; field.callRemote(); });
    field.live("keyup", function() {change = true; field.callRemote(); });

    setInterval(function() {
      if (change) {
        field.callRemote();
        change = false;
      }
    }, time * 1000);
  });
};