Skyfall
XBOX Cheat: LB, LT, RB, RT, LEFT, RIGHT, LEFT, RIGHT, LB, LT, RB, RT, LEFT, RIGHT, LEFT, RIGHT
PS3 Cheat: L1, L2, R1, R2, LEFT, RIGHT, LEFT, RIGHT, L1, L2, R1, R2, LEFT, RIGHT, LEFT, RIGHT
This might be the best cheat of them all. Upon entering, you will spawn high and the sky and start skydiving with no parachute, with the option of going into a nosedive or cruising in the air for an extended period of time. Once you hit the ground, the cheat is over. We prefer flying into the ocean and landing there, though.