Non, je ne regrette rien
"Non, je ne regrette rien" was a popular 20th century Earth song sung in the French language. When translated to English, its title meant "No, I do not regret anything."
During the 2310s, when Jean-Luc Picard was a child, his mother told Château Picard's computer to play this song in an attempt to calm her nervous son. As an adult, Picard recounted this memory to Agnes Jurati. (PIC: "Watcher")
In 2401, the song played on the bridge of the USS Stargazer as the Borg Queen boarded the ship and accessed its systems. (PIC: "The Star Gazer") Picard later realized the Borg Queen, recalling his conversation with Jurati about the song, was using the song as a message to him. (PIC: "Farewell")
While showing Jean-Luc a version of Château Picard in an alternate 2401, Q snapped his fingers, causing a record player to play a rendition of the song performed by Édith Piaf. (PIC: "Penance")