I can't remember very many things that are that great, but I do have some pretty sweet moments from my Halo 3 career.

One of the best moments is playing a very intense match of Team Slayer with the scores tied at 49. It basically ends with one friend betraying the other to not let the other team collect the point while I'm getting a kill somewhere else so the match ends and we win.

It was just the kind of thing that was so intense at the time and we were so overjoyed when we realized what happened.