So I watched the DVD(I have the 2-disc) again last night, and saw that after the credits, a sort of bonus area pops up. It's an image of Prime with a little bit of content: An Iron Man trailer, the first TF movie teaser trailer, and a 'Rise of the Autobots" music video. Not sure if that's the only way of accessing it, but on the main manu, there is that Autobot symbol on the lower right next to Scene Selections. Maybe there's someway of highlighting it?