Trylonian brain drain machine
A Trylonian brain drain machine was a piece of technology used by Trylonians to siphon off memories and information from someone. (COMIC: The Birthday Boy)
Trylonians used some machines to invade a planet, stealing knowledge from leaders and historians to use them against the invaded species. A few survivors stole a machine and took it on Earth to stole from someone ideas to counterattack. (COMIC: Convention Special)
On another occasion, Trylonians used a brain drain machine on the Eleventh Doctor to steal information about other species and conquer the universe, but the memories were so much for the supercomputer connected to the machine to handle that it exploded. (COMIC: The Birthday Boy)