If you haven't tried the
Flash version of
Portal, you should take a few minutes out of your day and check it out. If, however, you long for the full 3D experience that the full game offers you are in luck as the creators of the Flash version has
unleashed a map pack of the same levels for the real game. It's not a lie! The 40MB download will give you roughly 3.5 more hours of gameplay and contains 40+ levels.