Sponge Bob Squarepants: Battle For Bikini Bottom

Pause game play, then hold L + R and quickly press the following button
combinations:

Get 1,000 shiny objects:
Y, X, X, Y, Y, X, X, Y.

Get 10 Golden Spatulas:
X, Y, Y, X, X, Y, Y, X.

Refill health:
X(4 times), Y, X, Y, X, Y(4 times).

Get Bubble bowl power-up:
X, Y, X, Y, X, X, Y, Y.

Get Cruise bubble power-up:
Y, X, Y, X, Y, Y, X, X.

All monsters available in the gallery:
X, Y, X, Y, Y, X, Y, X.

Pantless SpongeBob:
X(4 times), Y, X, X, Y, X, Y, Y, X.

Big plankton:
Y(4 times), X, Y, X, Y, X(4 times).

Tiny people (fishes times):
Y(5 times), X, Y, X, Y, X, Y, X.

Concept art:
Go to the 3rd part of Bikini Bottom.
Collect 40,000 shiny objects. Go to the movie theater and hit R to go inside.
Hit A to see the art.