d = new Date();
hour = d.getHours();

if (hour < 12)
{
     document.write("<P ALIGN = 'CENTER'><B><FONT SIZE = 4>Good Morning!</FONT></B></P>");
}
else
if (hour < 17)
{
     document.write("<P ALIGN = 'CENTER'><B><FONT SIZE = 4>Good Afternoon!</FONT></B></P>");
}
else
{
     document.write("<P ALIGN = 'CENTER'><B><FONT SIZE = 4>Good Evening!</FONT></B></P>");
}

document.write("<P>");