bound = function () {

            if (this instanceof bound) {
                // 15.3.4.5.2 [[Construct]]
                // When the [[Construct]] internal method of a function object,
                // F that was created using the bind function is called with a
                // list of arguments ExtraArgs, the following steps are taken:
                // 1. Let target be the value of F's [[TargetFunction]]
                //   internal property.
                // 2. If target has no [[Construct]] internal method, a
                //   TypeError exception is thrown.
                // 3. Let boundArgs be the value of F's [[BoundArgs]] internal
                //   property.
                // 4. Let args be a new list containing the same values as the
                //   list boundArgs in the same order followed by the same
                //   values as the list ExtraArgs in the same order.
                // 5. Return the result of calling the [[Construct]] internal 
                //   method of target providing args as the arguments.

                var F = function(){};
                F.prototype = target.prototype;
                var self = new F;

                var result = target.apply(
                    self,
                    args.concat(slice.call(arguments))
                );
                if (result !== null && Object(result) === result)
                    return result;
                return self;

            } else {
                // 15.3.4.5.1 [[Call]]
                // When the [[Call]] internal method of a function object, F,
                // which was created using the bind function is called with a
                // this value and a list of arguments ExtraArgs, the following
                // steps are taken:
                // 1. Let boundArgs be the value of F's [[BoundArgs]] internal
                //   property.
                // 2. Let boundThis be the value of F's [[BoundThis]] internal
                //   property.
                // 3. Let target be the value of F's [[TargetFunction]] internal
                //   property.
                // 4. Let args be a new list containing the same values as the 
                //   list boundArgs in the same order followed by the same 
                //   values as the list ExtraArgs in the same order.
                // 5. Return the result of calling the [[Call]] internal method 
                //   of target providing boundThis as the this value and 
                //   providing args as the arguments.

                // equiv: target.call(this, ...boundArgs, ...args)
                return target.apply(
                    that,
                    args.concat(slice.call(arguments))
                );

            }

        }
Brings an environment as close to ECMAScript 5 compliance
as is possible with the facilities of erstwhile engines.

Annotated ES5: http://es5.github.com/ (specific links below)
ES5 Spec: http://www.ecma-international.org/publications/files/ECMA-ST/Ecma-262.pdf

@module