FYI:

Q: How do I change the network name of my Xbox?

A: There are four ways:

-Play Dead or Alive 3 and get a high-score in Survival Mode. Your current Xbox name will be one of the choices and any name you enter will become your new Xbox name.

-Create and save a game in Cel Damage. The name you give to your game will become your Xbox name (unverified by FAQ author).

-Create a new driver in MotoGP. The driver's name will become your Xbox name.

-Start a new game in "Championship Manager Season 01-02" (I think it's only out in Europe, I KNOW it's not out in America). Whatever you name your manager will be your Xbox's new name!