var PICSTART = 01;
var PICEND   = 11;

var pic = PICSTART + Math.floor(Math.random() * (PICEND - PICSTART));
var numprepend;

if (pic < 11)
{
	if (pic < 20)
	{
		if (pic < 11) numprepend = "0";
		else numprepend=""; 
	}
	else numprepend="";
} 

var msg = '<img src="images/ranpics/' + numprepend + pic + '.jpg" width="568" height="108" border="0" alt="" vspace="3"><br>';
document.writeln(msg);