The CBU-105 is one mean mother.
"And there is the Sensor Fuzed Weapon, designed to pulverize tanks, light armor and troops over a vast 30-acre landscape. The weapon is dropped from an airplane, opens in midair and releases 10 projectiles, which float down to the battlefield on tiny parachutes. When the projectiles are close to the ground, rocket motors spin them back up, where each of the 10 releases four warheads the size of soda cans, 40 in all. Each warhead is equipped with infrared and laser sensors. The infrared sensor scans the battlefield looking for preprogrammed heat signatures, like those emitted by tanks and other vehicles. Once a target is located, the laser sensor then guides the warhead into it. If the infrared sensor locates a tank or other vehicle, it fires an armor-piercing slug. But if no vehicles are spotted, the sensor detonates the warhead just above the ground to spray the battlefield with thousands of lethal fragments, or steel rain."
http://www.fas.org/man/dod-101/sys/dumb/cbu-97.htm