Vincent Vega doesn't have much luck with bathrooms: He emerges from the bathroom at Mia Wallace's place to find her overdosing. He is heavily criticised by Jules in Jimmy's bathroom for soiling the towel. He emerges from the bathroom at the coffee shop to find a robbery is occurring. After he shoots Brett, a guy comes out of the bathroom with a "hand cannon" and tries to shoot him. Finally, he emerges from the bathroom at Butch Coolidge's flat and is shot dead by Butch.
Kind of funny thing to notice. In the end credits, the Coffee Shop Manager is credited as just Coffee Shop. Quentin Tarantino said this was because when Tim Roth puts the gun to his head and says "Are you gonna be a hero?", the manager only says "No, I'm just a Coffee Shop-" before Tim Roth cuts him off and starts yelling again.
The weapons Butch goes through were all put in by Tarantino as an homage to some of his favorite movies of the past. The bat represents the four by four that Bufford Pusser used in "Walking Tall", the chainsaw was for what Leatherface uses in "The Texas Chainsaw Massacre", and the samurai sword was a general reference to Kurosawa movies.
The Statler Brothers song that Bruce Willis was singing along to on the way back to his apartment had a line "smoking cigarettes and watching Captain Kangaroo". In the movie Die Hard With a Vengeance, there's a scene in which he tells Samuel L. Jackson that he'd rather be home "smoking cigarettes and watching Captain Kangaroo".
In the scene where Butch is deciding to leave the place with the gimp there is a Killian's Irish Red sign on the right and Tennessee license plates on the left of the set. On the neon sign all of the letters of the sign are burnt out except KILL and ED. Butch can either decide to go to Tennessee and walk out the door on the left or he can go right to the sign that says KILL ZED. The letter Z comes from the keychain he is holding in his hand.
Most of the clocks in the pawnshop are set to 4:20. It is a widely acknowledged misconception that all of the clocks in the film are set to this time.
Phil LaMarr, who plays Marvin (the black guy, who gets shot in his face) is actually a member of the "MadTV" cast. Once MadTV had a skit called "Gump Fiction" (a crossover of "Forrest Gump" and "Pulp Fiction" - you gotta see this skit. Very funny.). In this skit he also plays Marvin, fearfully cowering like in the movie.
The lady that is shot in the street by Marcellus Wallace when he is trying to catch Butch is the very same lady that Mr. Pink pulls out of her car in Reservoir Dogs, another Quentin Tarantino film. Her name is Delorise Baker.
Tarantino originally wrote the role of Jules specifically for Samuel L. Jackson, however it was almost given to Paul Calderon after a great audition. When Jackson heard this, he flew to LA and re-auditioned, getting back the part he was supposed to play. Calderon ended up with a cameo as Paul, the bartender.