[Código Javascript] Fondo cambia cada 3 segundos

<SCRIPT LANGUAGE="JavaScript">
<!-- Start of JavaScript code --------
//
// Description: Randomly change background color every 5 seconds
// NewcWare 1997
// Author: Scott Newcomer 3/1997
// Email: nuke@bright.net
//
function setbackground()
{
    window.setTimeout( "setbackground()", 3000); // 5000 milliseconds delay
    var index = Math.round(Math.random() * 9);
    var ColorValue = "FFFFFF"; // default color - white (index = 0)
 
    if(index == 1)
        ColorValue = "FFCCCC"; //peach
    if(index == 2)
        ColorValue = "CCAFFF"; //violet
    if(index == 3)
        ColorValue = "A6BEFF"; //lt blue
    if(index == 4)
        ColorValue = "99FFFF"; //cyan
    if(index == 5)
        ColorValue = "D5CCBB"; //tan
    if(index == 6)
        ColorValue = "99FF99"; //lt green
    if(index == 7)
        ColorValue = "FFFF99"; //lt yellow
    if(index == 8 )
        ColorValue = "FFCC99"; //lt orange
    if(index == 9)
        ColorValue = "CCCCCC"; //lt grey

    document.bgColor=ColorValue;

}
// -- End of JavaScript code -------------- -->
</SCRIPT>