Laserson probe

The Laserson probe was a tool used for the modification or repair of just about any form of electronic technology, including weapons. It was both very powerful and very precisely summed up in one phase: "It can punch a fist-hole in six-inch armour plate or take the crystals from a snowflake one by one". Taren Capel used it to modify the Sandminer robots to kill, to try and burn out the Fourth Doctor's brain. The Doctor used it as a weapon against the robots. (DW: The Robots of Death)

The ancient cyborg Wesley Sparks threatened a number of people, including his fiancée Majenta Pryce, with a Laserson probe. In the end an android version of Wesley plunges that probe into the cyborg's chest, killing it. (DWM: Mortal Beloved)