Toshiko Sato claimed that The Prince of Tides was a pub at which she had participated in a pub quiz, in order to get information on Philoctetes without informing Jack Harkness about Mary. (TV: Greeks Bearing Gifts)
Behind the scenes
Toshiko pauses when naming the place: "the Prince of... Tides", likely indicating that the name came to her from the popular 1991 film of the same name.