Object.essence.js

/**
 * by Dmitry A. Soshnikov
 */

Object.defineProperty(Object, "essence", {
  value: function objectEssence(value) {
    var essence = {kind: Object.prototype.toString.call(value).slice(8, -1)};
    // use Object(value) just for shortness, it's less effective
    // than typeof value == "object" && value !== null || typeof value == "function"
    essence[value === Object(value) ? "object" : "primitive"] = true;
    return essence;
  }
});

var info = Object.essence;

// numbers
info(1);                  // {primitive: true, kind: "Number"}
info(new Number(1));      // {object:    true, kind: "Number"}

// null, undefined
info(null);               // {primitive: true, kind: "Null"}
info(undefined);          // {primitive: true, kind: "Undefined"}

// strings
info("1");                // {primitive: true, kind: "String"}
info(new String("1"));    // {object:    true, kind: "String"}

// regexp
info(/(?:)/);             // {object: true, kind: "RegExp"}

// array
info([]);                 // {object: true, kind: "Array"}

// object
info({});                 // {object: true, kind: "Object"}

(function () {
  info(arguments);        // {object: true, kind: "Arguments"}
})();

info(function () {});     // {object: true, kind: "Function"}

// etc.

I would replace
typeOf == "object" && value !== null || typeOf == "function"
to
value === Object(value)
just to make it shorter.

Yeah, good catch. Then typeof is not needed at all in such test. Although method call for Object should be slower, then using typeof operator (in theory, however, I didn't check it in implementations).