Maury Ginsberg played a character of the same name. The producers liked the actor's name so much that they decided to use it for his character.
The image of Earth that Q shows Janeway is the famous Blue Marble picture, a photograph taken in December 1972 by the crew of NASA spacecraft Apollo 17, upon returning to Earth following the final moon landing of the Apollo program.
The manner of Quinn's suicide, "Nogatch Hemlock," is an allusion to the execution-by-suicide of the Athenian teacher Socrates in 399 BCE. Having been convicted of "corruption of youth" (primarily by encouraging young men to avoid military service during a time of unjust war) and impiety against the national gods, he was given a choice between exile and ritual suicide. He chose the latter, which he performed by drinking a hemlock-based poison.
One of Quinn's hiding places from Q involves turning Voyager into a Christmas ornament. The same year that this episode aired (1996), Hallmark released a Voyager Christmas ornament.
While the image of Earth is the 1972 NASA 'Blue Marble,' it is oddly a mirror image reverse.