Can't afford the real Brad Pitt to star in your next film? Well, maybe soon, you can have his computer double for a fraction of the fee. Apparently the expertise to create exact screen replicas of humans is almost with us, meaning the people you see on screen may not be real at all. But can these avatars act? I guess that depends on who's weilding the mouse on the computer. Maybe the digital Pitt will be better than the real thing.