Once when some friends and I were playing Halo 2 online, we managed to stack all 4 of us on top of one another (using a sunroof in one of the bases). We timed it so that the person on the bottom would jump, then the guy on top of him, then the next and finally the guy on top, ultimately reaching a height equivalent to 4 regular jumps. The approaching enemy team would see a string of guys flying out of the top of the base, and would ideally be so confused by this sophisticated psychological tactic that they would retreat.
For some reason, we lost that match. But we had fun doing it so no matter.