Unlockable: Mini Games

Murrayball: Note: Do this before looking for the no-nosed man. Go to the Palace of Prostheses and look up the name Ryan J. Danzwithwolves in the files.  Murrayball will show up in Bonus Stuff.
Monkey Invaders: Complete the Monkey Kombat table for every stance. View it by pressing R2 in Monkey Kombat.

Unlockable: Bonus Ending

Complete the game and wait through the credits.