During the Vietnam War, Sam Johnson -- now a congressman from Texas -- spent seven years as a prisoner of war -- much of the time imprisoned, sometimes tortured, in the infamous camp ironically called the Hanoi Hilton.  When finally released, Johnson secretly absconded with what had been his only personal possessions -- a small metal cup and a tube of toothpaste.  Though of little material value, he says they meant everything to him when he had nothing else.  This is what it sounded like when Johnson recently donated the two items to the National Museum of American History.