function cantload() {
    img = document.getElementById("clustrMapsImg");
    img.onerror = null;
    img.src = "http://clustrmaps.com/images/clustrmaps-back-soon.jpg";
    document.getElementById("clustrMapsLink").href = "http://clustrmaps.com";
}
img = document.getElementById("clustrMapsImg");
img.onerror = cantload;