Jerry refers to two movies when they discuss what to do with Paul's body: Shallow Grave (1994) and "a movie I once saw about some guys who accidentally killed a hooker in Vegas and cut her up and transported her in suitcases". This is a referral to Very Bad Things (1998) where this scene takes place in a hotel room at a bachelor party, exactly the way Jerry describes it.
When Monica is talking to Bob by the lighthouse they are in bright late afternoon sunlight. Then Monica says, "I'll see ya Bob," as she turns to walk away. In the next wide shot they are both just dark silhouettes at a late sunset.
In the final scene when Monica meets the jogger who will presumably be her next victim, the jogger is wearing a T-Shirt that says "Pittsburg" and is outlined with the shape of the state of Pennsylvania. The city in Pennsylvania is spelled "Pittsburgh"; not "Pittsburg".