Whenever someone in the series said something that could be interpreted as being a dirty word, Yakko blew a kiss to the audience and said, "Good NIGHT, everybody."
Executive producer Steven Spielberg came up with the idea to have an original musical score in every episode of the series.
During the series' theme song, all of its characters proudly announce, "We have pay or play contracts". This is a Hollywood term which means that the performer is paid whether or not he or she plays a role. This was a big deal in the days of contract studio players.
The series, during its original run, was far more popular with teenagers and adults than with children. This became a problem early on, as The WB always placed it inside of their "Kids WB" programming block which eventually caused it to be canceled after five seasons because the sponsors of the block
felt uneasy about footing the bill for an audience to whom they could not sell any merchandise.
The Goodfeathers, who were parodies of the three main characters of the Warner Bros. film Goodfellas (1990), were made to reflect the personalities of the film's three main stars who played said main characters. Bobby, the blue pigeon, is meant to be a parody of Robert De Niro, Pesto, the purple pigeon, is meant to be a parody of Joe Pesci, and Squit, the gray pigeon, is meant to be a parody of Ray Liotta. Also, the Godpigeon is meant to be a parody of Marlon Brando from the film The Godfather (1972), right down to the character's incomprehensible speech pattern.