Effetto macchina da scrivere

<h2 id="fly">Thanks for visiting $Pubblicizza Forum!</h2>

<script type="text/javascript">

//Flying Letters script- by Matthias (info@freejavascripts.f2s.com)
// Modified by Twey for efficiency and compatibility
//For this script and more, visit Pubblicizza Forum: http://www.pubblicizzaforum.forumfree.net

//Configure message to display. Use "$" for linebreak
//By default, set to just grab the text from element with ID="fly"
message = document.getElementById("fly").innerHTML; // $ = taking a new line
distance = 50; // pixel(s)
speed = 200; // milliseconds

var txt="",
      num=0,
      num4=0,
      flyofle="",
      flyofwi="",
      flyofto="",
      fly=document.getElementById("fly");


function stfly() {
      for(i=0;i != message.length;i++) {
              if(message.charAt(i) != "$")
                      txt += "<span style='position:relative;visibility:hidden;' id='n"+i+"'>"+message.charAt(i)+"<\/span>";
              else
                      txt += "<br>";
      }
      fly.innerHTML = txt;
      txt = "";
      flyofle = fly.offsetLeft;
      flyofwi = fly.offsetWidth;
      flyofto = fly.offsetTop;
      fly2b();
}

function fly2b() {
      if(num4 != message.length) {
              if(message.charAt(num4) != "$") {
                      var then = document.getElementById("n" + num4);
                      then.style.left = flyofle - then.offsetLeft + flyofwi / 2;
                      then.style.top = flyofto - then.offsetTop + distance;
                      fly3(then.id, parseInt(then.style.left), parseInt(then.style.left) / 5, parseInt(then.style.top), parseInt(then.style.top) / 5);
              }
              num4++;
              setTimeout("fly2b()", speed);
      }
}

function fly3(target,lef2,num2,top2,num3) {
      if((Math.floor(top2) != 0 && Math.floor(top2) != -1) || (Math.floor(lef2) != 0 && Math.floor(lef2) != -1)) {
              if(lef2 >= 0)
                      lef2 -= num2;
              else
                      lef2 += num2 * -1;
              if(Math.floor(lef2) != -1) {
                      document.getElementById(target).style.visibility = "visible";
                      document.getElementById(target).style.left = Math.floor(lef2);
              } else {
                      document.getElementById(target).style.visibility = "visible";
                      document.getElementById(target).style.left = Math.floor(lef2 + 1);
              }
              if(lef2 >= 0)
                      top2 -= num3
              else
                      top2 += num3 * -1;
              if(Math.floor(top2) != -1)
                      document.getElementById(target).style.top = Math.floor(top2);
              else
                      document.getElementById(target).style.top = Math.floor(top2 + 1);
              setTimeout("fly3('"+target+"',"+lef2+","+num2+","+top2+","+num3+")",50)
      }
}

stfly()

</script>