Teenage Mutant Ninja Turtles
aka: Teenage Mutant Hero Turtles

Cheat mode:
Press Up(2), Down(2), Left, Right, Left, Right, A, B, A, B, Start at the title screen. Note: For two players, press Up(2), Down(2), Left, Right, Left, Right, A, B, A, B, Select(2), Start.

Switch boomerangs:
Throw boomerangs and switch turtles while they are in-flight. The new turtle will catch the boomerangs and place them in his inventory.