Easter egg: In the special features under the "Philosophy of Time Travel Book" in scroll through until you see a man with a target around him. Press the up button and the target is highlighted. Press enter.
Easter egg: Go to the 'Special Features' and click on 'The Philosophy of Time Travel'. Go through the book's pages until you get to the skeleton with the arrow coming from it's chest. Press up and a solid black arrow within the arrow will appear. Press Enter and you will see a hidden trailer.
Easter egg: In the special features under the "Philosophy of Time Travel Book" in Appendix A, if you use a DVD-ROM and click on the circles in the middle of the drawing a deleted scene is shown.