var today  = new Date();
var day    = today.getDay();
var pfad   = "tpics";
var prefix = "bild_des_tages_";
var arday  = new Array(
pfad+"/01.jpg",
pfad+"/02.jpg",
pfad+"/03.jpg",
pfad+"/04.jpg",
pfad+"/05.jpg",
pfad+"/06.jpg",
pfad+"/07.jpg");
document.write("<img src='" + arday[day] + "' alt='Bild des Tages'>\n");