The Blue Boy
From Memory Alpha, the free Star Trek reference
The Blue Boy is a painting by the British painter Thomas Gainsborough, created in the 18th century.
Professor James Moriarty kept a replica of the painting in his laboratory in Data's Sherlock Holmes holoprogram. (TNG: "Elementary, Dear Data")
Wesley Crusher's outfit on the holodeck in TNG: "Hollow Pursuits" was based on The Blue Boy.
