Electro knife
From Tardis Wiki, the free Doctor Who reference
The Electro knife was a weapon provided to agents of the Space Security Service. It had a blade made from diametal, the hardest substance in the universe. In the handle of the knife was a Grauman power unit which, when switched on, the blade was sawn back and forth at high speed and could cut through inch-thick hardened steel. When thrown, it was propelled at the speed of a bullet. (PROSE: The Outlaw Planet) The weight of the electro knife was ten ounces, its length was twelve inches, its throwing range was one hundred yards and the power unit life before it needed recharging was three hours. (PROSE: Top Secret)
