- Grim Fandango reference
In Le Chuck's lair, look closely at the pillars made from skulls. One of the faces is that of Manny Calavera's head.

- Sam And Max series reference
Play the game in Classic Style mode, and go to the monkey head entrance. You can see Sam and Max idols.

- Trophies
Successfully complete one of the following tasks to get a trophy:

Bronze Trophies
Recordkeeper	Acquire all of the notes and memos on Monkey Island.
Escape Artist	Escape from the Monkey Island Cannibals' hut 5 times.
Ten Minutes Later...	Have Guybrush drown.
Human Cannonball	Finish the entire game in under 3 hours.
Marooned Everyone	Use one save slot to play both endings.
Old School	Switch to classic mode at least once.
Determined	Don't use any hints to finish the game.
Silver Trophies
The Journey	Finish Part Two
Under Monkey Island	Finish Part Three
Sharp Tongue	Learn all of the insults from the pirates.
The Three Trials	Finish Part One
Gold Trophies
Guybrush Kicks Butt	Finish Last Part

- Maniac Mansion 2 reference
Play the game in Special Style mode, and go to the monkey head entrance. You can see a Purple Tentacle idol.