Ted Kaczynski lived inside a 10-by-12-ft. (3 by 3.6 m) shack he built near Lincoln, Mont., for almost two decades. It was a bombmaking, manifesto-writing shack that enabled the Unabomber to terrorize U.S. citizens through mail bombs for years. The one-room cabin — which included books, a workbench, a potbellied stove and plenty of explosive-making materials — was almost demolished after Kaczynski was arrested in 1996. But at the last minute, it was saved and was later put on display at the Newseum in Washington, D.C., just blocks from the FBI headquarters where the Unabomber was the target of an immense investigation for 17 years.