Elephant flipping

Although the Elephant is the only indestructible human land vehicle in Halo 3, it is possible to flip an Elephant over, unlocking an interesting Easter Egg.

Gravity Lift Method
The easiest way to flip an Elephant is to spawn a closed drop pod in the cockpit and throw down a grav lift right near it.

Fusion Coil Method
Firstly, put all the Fusion Coils and Plasma Batteries on the back of the Elephant (on Forge). Then set the Plasma Batteries and Fusion Coil's settings so every number is the highest possible. Then stand back and shoot one of the Fusion Coil and watch the fireworks.

Scorpion Method
It is also possible to use a Scorpion to flip the Elephant. In Forge, spawn a Scorpion and move it to the rear of the Elephant. While in edit mode, hover the Scorpion in the back of the Elephant wedging it between the floor and the walkways on the second level. Once the Scorpion is wedged in tightly, pull back as if to move the scorpion, if wedged in enough, the Elephant will be able to be raised off the ground. While in the air, rotate the Elephant using the controls to flip.

Run over Method
Another way of flipping an Elephant is to drive one towards and partially over the other, then get out and drive the other one forward until it flips it over.

Results
The Gravity Lift Method will just flip it but the Fusion Coil Method will send it flying in the air and will not land on the floor and stop flipping for a while. Once the Elephant has landed, go up to it, and instead of the classic flip message it will say "Hold RB to flip...wait, what? How did you do that".