Código Solucion 7 -html + js:
Ver original---------------------------------------------------(HTML)
<BODY onload="pingpong();">
---------------------------------------------------(JS)
<script language="JavaScript">
var yourwords = "Sistemas operativos, Base de datos, Diseño Web";
var buffer1=" ";
var buffer2=" ";
var message1=buffer1+yourwords+buffer2;
var dir = "left";
var speed = 75;
function pingpong()
{
if (dir == "left")
{
message2=message1.substring(2,message1.length)+" ";
window.status=message2;
setTimeout("pingpong();",speed);
message1=message2;
if (message1.substring(0,1) == "S") dir="right";
}
else
{
message2=" "+message1.substring(0,message1.length-2);
window.status=message2;
setTimeout("pingpong();",speed);
message1=message2;
if (message1.substring(message1.length-1,message1.length) == "b") dir="left";
}
}
</script>