<form>
  <input type="submit" disabled="disabled">
</form>

var q = q ? q : new Object();
/* create document element */
q.CreateElement = function(tagName) {
    return document.createElement(tagName);
};
/* set element attribute */
q.SetAttribute = function(element, attName, attValue) {
    return element.setAttribute(attName, attValue);
};
/* append element to given parent */
q.AppendChild = function(parent, newChild) {
    return parent.appendChild(newChild);
};
/* set element class name */
q.ClassName = function(element, className) {
    return element.className = className;
};
/* fetch source element of the event */
q.GetTarget = function(ev) {
    var target;
    if (!ev) var ev = window.event;
    if (ev.target) target = ev.target;
    else if (ev.srcElement) target = ev.srcElement;
    if (target.nodeType == 3)
        target = target.parentNode;
    return target;
};
/* button click event */
q.buttonClick = function(event) {
	/*
	as we cannot pass parameter with the event (possible in IE Browsers),
	checking the value of source element.
	*/
    if (q.GetTarget(event).value.indexOf("Add") == 0) {
        var newBtn = q.CreateElement("input");
        q.SetAttribute(newBtn, "value", "Delete");
        q.SetAttribute(newBtn, "type", "button"); /* set type of the input */
		/* attach event to new button */
        if (newBtn.addEventListener) { /* if FF */
            newBtn.addEventListener('click', q.buttonClick, event);
        } else { /* if IE */
            newBtn.attachEvent('onclick', q.buttonClick);
        }
        q.ClassName(newBtn, "q");
        q.AppendChild(document.body, newBtn);
    }
    else {
        var btns = document.getElementsByTagName("INPUT");
        var tmp; /* temporary value */
        while (tmp = Math.floor(Math.random() * 10)) {
            if (tmp < btns.length) /* boosting */ {
				/*
					check if the button has no values as "Add" and
					not the sender itself, remove it
				*/
                if (btns[tmp].value.indexOf("Add") != 0 && btns[tmp] != q.GetTarget(event)) {
                    document.body.removeChild(btns[tmp]);
                    break; /* end the loop */
                }
            }
        }
    }
};