River Song's scanner
This Scanner was a device that River Song used frequently. It was branded "Magpie Electricals".
River used it to scan Amy Pond and determine she was dying. (DW: 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. (DW: 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; (DW: The Impossible Astronaut) and to learn that the astronaut suit that the her younger self had escaped from was augmented with alien technology. (DW: Day of the Moon)