Before Tobey Maguire was called in to voice Spider-Man, Josh Keaton (best known for voicing Spider-Man in The Spectacular Spider-Man) was called in to replace him. When Tobey was brought in to reprise the role, Josh's audio was instead used for Harry Osborn in the playable Green Goblin mode.
There is an unused web item in the Game Boy Advance version of the game called the "Blind Web". When used, the screen flashes white and all of the enemies close to Spider-Man become immobilized in web.
If you put in the cheat code "girlnextdoor" you can play the game as Mary Jane Watson. At the end of the game, where Spider-Man and Mary Jane usually kiss, Mary Jane will kiss herself. This code was removed from later versions of the game, presumably because of the lesbian kiss in an E-rated game.