Here you are: this page can be reached from myown511.htm on a specific day in march using the 'correct' password... the one that would allow you to enter the 'devious' javascript page on 20 march.
Here, below, you can see a more complex form of date encryption... ready to be inserted in the code in the page you come from. But I did not wanted to make things too complicated (they will be complicated enough when we'll go together along the 'higher' javascript protections paths)... and I did NOT use it in my code.

In fact, the code below can be used to create a 'rotating' secret access page... if you find this interesting and if you reach the devious page (which is fairly easy now) and if you write a contribution on this kind of stuff to be published there, I will publish there the COMPLETE implementation of this kind of trick... at work!

 function passEncode(form)
  {
    vournt(form.password.value);
  }

  function vournt(passwd)
  {
    var Key = getKey();
    var Ret = encode (passwd, Key);
    location = baseurl + Ret + "/";
  }

  function getKey()
  {
    if (codeoverride == -1)
    {
      var months = new Array();
      months[0]=31;
      months[1]=28;
      months[2]=31;
      months[3]=30;
      months[4]=31;
      months[5]=30;
      months[6]=31;
      months[7]=31;
      months[8]=30;
      months[9]=31;
      months[10]=30;
      months[11]=31;

      var dater = new Date();
      var Key = 0;
      for (var count = 0; count < dater.getMonth();count++)
      {
        Key = Key + months[count];
      }
      Key += dater.getDate();

      if (changetype == "DAYS")
      {
        Key = Key / changen;
      }else if (changetype == "WEEKS"){
        Key = Key / 7;
        Key = Key / changen;
      }else{
        Key = dater.getMonth() + (dater.getYear() * 12);
        Key = Key / changen;
      }
      dater = null;
    }else{
      Key = codeoverride;
    }
    Key = Math.floor(Key);
    return (Key);
  }