[рони]

Артист,

function xml(method, post, ref, functions) {
    var xhr = new XMLHttpRequest;
    xhr.withCredentials = true;
    xhr.onreadystatechange = functions;
    xhr.open(method, ref, post);
    xhr.send(null)
}
xml("GET", true, "http://www.site.ru", function() {
    if (this.readyState != 4) return;
    alert(this.responseText)
});