// Dialog constructor
function Dialog(id, html) {
    this.id = id;
    this.div = new Element('div', { 'id': id, 'class': 'dialog' } );
    this.div.insert(html);
    this.div.dialog = this;
}

// "instance" methods
Dialog.prototype.open = function() {    
    document.body.appendChild(this.div);
    window.scrollTo(0,0);
}

Dialog.prototype.close = function() {        
    Dialog.close(this.id);
}

// "static" methods
Dialog.close = function(idToClose) {
    $(idToClose).remove();
}