Rose laughed, shaking her head. "I'm not telling you exactly how it works, Adam." She paused. "Though when you go back, you might look up a Captain Jack Harkness, if he's around. He had one a lot like this, and he's still in your universe."
She opened the battered cover, showing the small screens of the computer. "It's a computer with address book, life-sign tracker, teleport, and other features which I'm not going into." She looked over at him, a half-smile on her face. "Takes too long."