Magazines that characters read are often references to later episodes or plotlines for upcoming episodes in the season.
Every episode has the sound of ice cubes clinking on glass.
Woodhouse's name is a reference to famed British writer P.G. Wodehouse, best known for his series of Jeeves and Wooster stories, about a superlative British butler and his rather dimwitted employer.
In most episodes, you can find Pam's (Amber Nash's) name in graffiti on the walls.