Dimension Cannon
From Tardis Wiki, the free Doctor Who reference
The Dimension Cannon was a device used in Pete's World invented by Torchwood. Rose Tyler used the device several times to try find the Doctor. Mickey and Jackie also used it to help save Sarah-Jane Smith.
The Device did not used to work but as the Darkness aproached it started working as the walls of time were breaking. After defeating Davros the Dimmension Cannon will probably not work.
