function imagesRandomiser() {
	var TOTAL_IMAGES = 40;
	var imageHistory = "|";
	var p = "";
	for(var i = 0; i < 5; i++) {
		var id = Math.floor(Math.random() * TOTAL_IMAGES) + 1;
		while(imageHistory.indexOf("|" + id + "|") >= 0) {
			id++;
			if(id > TOTAL_IMAGES) {
				id = 1;
			}
		}
		imageHistory += id + "|";
		if(String(id).length == 1) {
			id = "0" + id;
		}
		p += '<img src="images/portfoliobanner/port_' + id + '.jpg" width="136" height="100" border="0">';
	}
	return p;
}


document.write(imagesRandomiser());