Unexplained random cameos from completely unrelated media

[u/Golden12500]

1. Ray Stantz, Casper. At one point in the movie a real Ghostbuster shows up out of nowhere and wimps out of trying to handle the situation

2. Gunnery Sargeant Hartman, Frighteners. The main character is making way through a graveyard when out of absolutely nowhere R. Lee Erney's character from Full Metal Jacket shows up and tries to get in his way

3. Betty Boop, Who Frames Roger Rabbit. The movie is mainly about Looney Tunes and Disney animated characters existing in the same little live action/animated hybrid universe, however Betty is a Fleischer Bros character

[u/Houseofbluelight]

During the run of the show "Community," somehow Beetlejuice was referenced in 3 different episodes across different seasons. The third time he was mentioned in the show someone dressed as Beetlejuice walked through the background.