function random_banner() {
banner = new Array();
banner[0]="bnr_100531_koolau.gif";
banner[1]="bnr_100630_ts.jpg";
message = new Array();
message[0]="Koolau Guitar and Ukulele Company";
message[1]="入門機からカスタムメイドまでウクレレ工房 ティーズウクレレ";
link = new Array();
link[0] = "http://www.koolauukulele.com/";
link[1] = "http://www.ukes.jp/";
rand = Math.floor(Math.random()*banner.length);
document.write("<p><a target='_blank' href="+link[rand]+"><img alt="+message[rand]+" src="+banner[rand]+" style='border-style:none'></a></p>");
}