PaRappa The Rapper cheats and cheat codes for Playstation

Unlock extra stage:
Finish each stage with a "Cool" ranking. An extra stage with Sunny
Funny and Katy Kat dancing on a table will be unlocked.

Change Parappa's voice
Finish the first 2 stages with a "Cool" ranking. Then, press X, X, X, 
Triangle, Circle, Triangle, Square, Swquare, Right, Left, Square, X 
and complete the next stage. On the stage 4, push X, Square, Triangle, 
Circle, X to allow Parappa's voice to be changed. Hold R1 and push 
Triangle or Circle to choose between the voices of the other characters 
in the game. 


Unlock Beetle
To play as the beetle that you face on the last stage, 
Complete the 1st board with Cool! ranking, 
Complete the 2nd board on Good! ranking
Complete the 3rd board on Good! ranking
Complete the 4th board on Cool! ranking
Complete the 5th board on Cool! ranking
and finally beat the last stage and reach Good! ranking.

But the Cool! Word has to be blinking and you unlocked a new game 
that you can choose called, the Beetle Rappa!