Go to Metalis at 2:42-2:47 am and go to the titanium bolt area, there should be a teleporter. Go in the teleporter and you will end up in the High Impact Games Treehouse. Here you can see things that did not make it into the game and play Clank Challenges. You could also test out the Miniturret Glove, watch galleries, and smash stuff. There was even a giant statue of Ratchet!