toType.js

// Based on Angus Croll's http://javascriptweblog.wordpress.com/2011/08/08/fixing-the-javascript-typeof-operator/
// Also available at http://jsfiddle.net/7xAqT/

Object.toType = (function() {
    var global = this,
        toString = Object.prototype.toString;
    return function(obj) {
        if (obj === global) {
            return "Global";
        }
        var type = typeof obj;
        return type == "object" ? toString.call(obj).slice(8, -1) : type;
    }
})();

alert([
    Object.toType(5),
    Object.toType(new Number(5)),
    Object.toType(null),
    Object.toType(undefined),
    Object.toType({}),
    Object.toType([])
    ].join("\n"));