Things learned in JavaScript and they are good. Sourced mainly from Paul Irish (watched his video a while ago but I wanted to get it down in code).

asynchronous.js

// Asynchronous Recursion.
(function me() {
    doStuff();
    setTimeout(me, 100);
}());

// (1) Better than the alternative that never ends.
setInterval(function () { ... }, 100);

// Ajax example.
(function loopsiloopsiloo () {
    doStuff;
    $("#Update").load("awesomething.php", function () {
        loopsiloopsiloo();
    });
}());

Function.js

// new Function.
var x = (new Function("return " + data))();

// (1) Better than using eval.
var x = eval("(" + data + ")");

IIFE.js

// Immediately-Invoked Function Expression (IIFE).
(function (window, document, undefined) {
    ...
}(this, this.document));


// (1) When minified it becomes.
(function (A, B, C) {
    ...
}(this, this.document));

// (2) Ensures that undefined comparisons are correct. For example you might have...
undefined = true;

// (3) Benefits scope traversal because it only had to search the local scope for the variable.