So, I found this video on YouTube, where the uploader claims to have found a hidden code in Black Ops, may be interesting. Warning: Don't watch if you haven't completed the game yet
Link to the video: http://www.youtube.com/watch?v=PLZlfHGo-Ro&feature=player_embedded
For those who want to know the message of the code, withouth having to watch the video, it basicly says: "Reznov is dead, or is he dead? There was no body, is he who he says he is?"