A bit of trivia re: creepy cab driver.
The actress's name is Angela Jones who starred in a short written and directed by Reb Braddock entitled "Curdled" made in 1991. It was about a young girl who witnesses a death and is intrigued, even excited by it. The short was made into a feature in 1996 where Angela reprised her role alongside Billy Baldwin as a serial killer. The '96 feature was executive produced by Quentin Tarintino. QT must have seen the short and wanted to pay homage to the role and so hired Angela to play the cab driver.
Theory on what's inside the case:
I can't remember where I heard it but I did a bit of research and it is an interesting theory. One of the chakras is believed to located right at the base of the neck and some ancient Egyptian cultures believed that the soul could be accessed through this "gateway". We see a band-aid at the base of Marsellus's neck in multiple scenes. The theory I remember hearing is that Marsellus's soul was extracted from his body and now resides in the briefcase. Vincent and Jules are charged with the task of returning it to him.
