JoJo's Bizarre Adventure: Stone Ocean gives a Spoiling Shout-Out to the film during the "Jail House Lock" arc. A bunch of Green Dolphin Street prisoners are watching The Sixth Sense, only for Jolyne to recognize the movie, saying she's seen it a thousand times as a kid, and tell the others that, "Bruce Willis is actually dead, and he's a ghost! That's how it ends." The moviegoers look less than pleased by her telling them that.
The Lion King 1 ½: When Timon and Pumbaa try to make their new home in the Elephant Graveyard, they witness a violent battle (actually Mufasa saving his son from the hyenas) and a scared Timon whispers "I see carnivores".
Undercover Brother: The title character, in order to go undercover in a MegaCorp of white people, is subjected to the "Caucasian Vision" in order to suck in as much Brown Note-like 'white culture' as possible in a short amount of time. When the procedure is about to be over, Undercover Brother mutters "I see white people".
The Dresden Files: In Ghost Story the inevitable "I see dead people" reference goes to Fitz, who cannot actually see them but has been hearing them an awful lot lately.
The Darkside Detective: A Fumble in the Dark has a twist on "I see dead people", spoken by Raxa as she introduces the ghost she's seeing in the romantic sense.
Warcraft III: The map-reveal cheat is "iseedeadpeople", while one of the Necromancer's Stop Poking Me! lines is "I see undead people".
RebelTaxi: In "5 Cartoonists Who Regret Their Work", he describes Bruce Willis in an interview for Rugrats Go Wild! as looking "deader than the entirety of The Sixth Sense."
The plot of the South Park episode "Dead Celebrities" is this, where Ike is haunted by various celebrities who died in the summer of 2009. He even ends up saying "I see dead celebrities" in the episode.
