License plates read "D34D 1574ND" which translates from leet speak to "Dead Island".
On various bookshelves throughout the game, you can find a book titled "Dead Island: A True Story".
The challenge "YA RLY" is a reference to the popular internet meme "O RLY?".
The achievement/trophy "Somebody set up us the bomb" is a reference to the popular internet meme "All your base are belong to us".
There is a long and arduos easter egg which includes the collection, and specific placement of several colored skulls, sucessfully completing this easter egg results in Developer's Mods.
In the beginning, when you leave your room and enter the one down the hall left of you, you will find the couple from the trailer, dead, of course.
Beer machines all over Banoi, especially found in bars on the first map, have the trademark "Heineken" logo on them, but instead read "Dead Islander".
You can find packets of tobacco scattered around the floor (there are lots located where you have to find flares in Act I) that are clearly modelled after Golden Virginia brand rolling tobacco.
In some places women can be heard speaking in Polish. They pray a "Hail Mary" prayer: "Zdrowaś Maryjo, łaski pełna, Pan z tobą, błogosławionaś ty między niewiastami i błogosławiony owoc żywota twojego, Jezus. Święta Maryjo, matko boża, módl się za nami grzesznymi teraz i w godzinę śmierci naszej. Amen."
Copy of "Fakt", the largest Polish tabloid, can be found in Act I. Headline on front page says: "Ile ofiar zbierze zaraza?" ("How many victims will gather the plague?") "Fakt" is known for publishing absurd articles, i.e. "I do not sleep because I keep dresser" ("Nie śpię, bo trzymam kredens") or "Quilt wanted to strangle me" ("Kołdra chciała mnie udusić").
Poster with face of Adrian Ciszewski, producer of "Dead Island", and sign "VOTE!" can be found in cabin in Act I and Mohakin's cabin in Act III.
There is an obvious reference to the american serial killer Ted Bundy in Act 1. The man in the swimming pool surrounded by bodies is named Ted.B
The achievement "Tis but a flesh wound" is a reference to the famous "Black Knight" scene from "Monty Python and the Holy Grail", in which King Arthur, played by Graham Chapman, is fighting the Black Knight, played by John Cleese, and is able to cut off both of his arms. When King Arthur declares victory, the Black Knight argues that the loss of his limbs is "Just a flesh wound."
There is a weapon called "Pick of Destiny", this is possibly a reference to the 2006 American comedy/rock musical "Tenacious D in The Pick of Destiny".
The quest "Toy Story" is a reference to the popular children's movie franchise "Toy Story".
The achievement/trophy "Cardio" which is a possible reference to the 2009 American zombie comedy film"Zombieland", as Columbus' first rule is "Cardio".
In the Laboratory, there is a janitor named Joel Dirt, which is a reference to the 2001 American comedy film"Joe Dirt".
The weapon "Zed's Demise" is a reference to the 1994 film "Pulp Fiction" by Quentin Tarantino.
While in the jungle during Act III, a man named Jason can be seen fighting the undead with a machete while wearing a hockey mask. Jason is likely a reference to Jason Voorhees, the fictional character from the"Friday the 13th" series of slasher films. (of further note, Jason's cabin references several other slasher films: The Chainsaw from Texas Chainsaw Massacre, the Boiler Room from A Nightmare on Elm Street, and the stick puppet shrines from Blair Witch Project.)
The quest "Full Metal Jacket" is a reference to the 1987 war film of the same name.
The achievement/trophy "How many days exactly?" could be a reference to the movie "28 Days Later..."
Character named Antonio Margarete is a reference to the 2009 film "Inglourious Basterds" by Quentin Tarantino. Antonio Margarete was a fake name of Eli Roth's character which tried to fool Colonel Hans Landa.