River Song's scanner
River Song made frequent use of a scanner branded "Magpie Electricals". She used it to scan Amy Pond and determine she was dying. (TV: Flesh and Stone) She scanned the Underhenge and found its pillars were transmitting a signal throughout time and space and later, that there were tens of thousand of alien ships in space. (TV: The Pandorica Opens)
On other occasions, River used the scanner to let her know there were extensive tunnels beneath Florida that extended around the world, to open a locked door, (TV: The Impossible Astronaut) and to learn that the astronaut suit that her younger self had escaped from was augmented with alien technology. (TV: Day of the Moon)