good worker

script.js

var paralellAjax = cw(function(url,callback){
    var ajax = new XMLHttpRequest();
    ajax.onreadystatechange = function(resp){
        if(ajax.readyState === 4 && ajax.status === 200) {
            calback(JSON.stringify(ajax.response));
        }
	}
	ajax.open('GET',url,true);
    ajax.send();
});