Grauman power unit
From Tardis Wiki, the free Doctor Who reference
The handle of the electro knife contained a Grauman power unit which, when switched on, caused the blade to saw back and forth at high speed and could cut through inch-thick hardened steel. (PROSE: The Outlaw Planet [+]Loading...["The Outlaw Planet (short story)"], Top Secret [+]Loading...["Top Secret (feature)"])
