Chao Puzzle VMU Game (Sonic Adventure):

Note: This trick requires two controllers, one into port A and the other into port D. Insert a VMU into controller D and load Sonic Adventure. Press Start controller D and "Chao Puzzle" should appear on the VMU. Press Start on controller A to pause the game before playing Chao Puzzle. Note: Allowing the game to continue while playing the Chao Puzzle will cause it to freeze.