function RandomNumber()
{
var today = new Date();
var num= Math.abs(Math.sin(today.getTime()/1000));
return num;
}
function RandomFlash() {
var x = RandomNumber() * 100;
if (x > 80) {
document.write("");
}
else if (x > 60) {
document.write("");
}
else if (x >40) {
document.write("");
}
else if (x > 20) {
document.write("");
}
else {
document.write("");
}
}
RandomFlash();