MOAB Bomb (Episode: The Power of Fear)

The most massive conventional weapon in the U.S. arsenal, the Massive Ordnance Air Blast bomb (the GBU-43/B) weighs 21,000 pounds and carries nine tons of H-6 explosive. With such mass and size -- it's 30 feet long and nearly 4 feet across -- the bomb can only be deployed from the spacious rear door of cargo aircraft.

The MOAB uses a GPS system to guide it to targets, but with a lethal blast radius of 400 feet, it can hardly be considered a precision weapon. Pound for pound it is far less effective than multiple, smaller yield bombs, but the psychological effects -- which include an extensive blast wave and a nuclear bomb-like mushroom cloud -- are incomparably terrifying.