Magneton Scanner
A magneton scanner was a 24th century engineering tool that is one of the most thorough scanning devices aboard Federation starships.
In an alternate reality in 2371, the USS Voyager used a magneton scan to detect subspace fractures on a class M planet in the Delta Quadrant. (VOY: "Time and Again")
Later in 2371, the Voyager crew tried to scan for a non-corporeal alien life form moving from one crewman to another using a magneton scanner, as Paris suggested it was the most thorough scanning device aboard, but it was unsuccessful. (VOY: "Cathexis")
Later that year, B'Elanna Torres suggested to Chell that a magneton scanner would degauss the transporter room in about five minutes; a lot faster then the micro-resonator he was using, but Tuvok told him it would teach him "patience". (VOY: "Learning Curve")
In 2373, when Captain Janeway was near death, she hallucinated that Torres used a Magneton scanner to search for her remaining presence aboard the ship, if there was anyway to help her. But this later turned to be an alien-induced near-death-experience. (VOY: "Coda")