Leela temporarily takes over as resident bureaucrat while Hermes is gone and receives a notice written in an alien language. Not being able to read the letter she hides it behind a plant. The letter reads: “Need extra cash? Melt down your old, unwanted humans. We pay top dollar!”
The number of the “cubicle room”, 729, is a cube ($ 9^3 = 729 $).
The cubicle room itself and Bender's statement are references to the 1997 movie Cube. The quote may also be a reference to Bender's serial number, which is expressible as the sum of two cubes.
The way Hermes' cubicle is transported to the lower layer is a reference to the popular puzzle Rubik's Cube.
A photography store seen in Tijuana named "Adobe Photo Shoppe" refers to the popular photo editing software Photoshop.
Bender said when a robot dies, he is downloaded into a backup robot, but in the episode The Honking when Bender's Uncle Vladimir died they buried his body along with all the other robots in the graveyard. It is possible though that backup programs weren't added until after Uncle Vladimir was built.
Bender mentions that he has been to Italy last week which indicates that the amount of time that passed on Futurama is the same as in reality since both episodes and their airdates were a week apart.
Bender said when a robot dies, he is downloaded into a backup robot. This could be a reference to the human cylons in battlestar galactica, which when upon dying are downloaded into a new backup body,
The ending song is "You Are My Little Bird", by Elizabeth Mitchell.
The episode's title is a play on "lethal injection", a form of execution.
The bureaucrat in the cubicle next to Hermes' is a caricature of Paul Lynde, who appeared frequently on the game show The Hollywood Squares in the center square.
In Tijuana, we see a business called Ay Cantina Turner, referencing the singers Ike and Tina Turner.