jsPerform.preload.js - preload certain element at the right time, such as user login;

jsPerform.preload.js

var preload;
if ( /*@cc_on!@*/ false) { // IE sniffing with conditional comments
    preload = function (file) {
        new Image().src = file;
    };
} else {
    preload = function (file) {
        var obj = document.createElement('object'),
            body = document.body;

        obj.width = 0;// make the file invisible
        obj.height = 0;
        obj.data = file;
        body.appendChild(obj);
    };
}
preload('my_web_worker.js');