I have not watched 8 1/2 but I have been searching youtube for videos of the movie. I have noticed, just like everyone else, similarities to this movie. One of the movies that really stuck out to me was Woody Allen's Stardust Memories. It is a movie that Woody Allen made that parodies Federico's 8 1/2. Woody Allen is no stranger to existentialism and and mocking other films. However he does a job paying homage to the original films he mocks. Take a look at the the openings to both of the films.
You can easily see the similarities in both of these openings.
Also an added bonus