while playing game enter
DOWN on the Right Analog + UP on the Left Analog, X, CIRCLE, SQUARE, TRIANGLE
To do this, wait for a long time and you will see Jack kneeling down and weaving something. After that, he'll wear his straw hat.
Caution: If you exit the section you are present in, the hat will disappear.
Hit the chickens in the first level to make 'em bigger. To stop them, just block 'till they shrink to normal size.
Beat the game on all difficulty levels.