I have have had several names each for a specific clan, once I leave a clan I usually change my gamer tag referring to a fresh start. Ill tell you some of my previous names and their significance.
ammo - refers to taken the first letter of my first name, adam, and the first and second letter of my last name, morrisey, used this in my first clan
flash - in cod2 i was known for having a quick trigger with a bolt action rifle, used this in my second cod2 clan.
shadow.ghost - being a silent and deadly killer, used this in bf2142
skinny - I was in a clan that was dedicated to the 101st airborne, and we had to choose a name from an actual person who fought in the 101st airborne during world war 2, I chose wayne "skinny" sisk. This was mainly a cod2 Tactical clan, lost a few members, tried cod4, then disbanded.
swagger - based this off the character from the movie shooter, bobby lee swagger, used this name for most of my pubbing time in cod4 and the beginning months of cod5 till another clan i joined disbanded.
strand - there is actually no real signifcance as to why i chose this name, I was just wearing a shirt the day i felt the urge to change my name, and on it said "strand.mfg", I thought and concluded that it sounded cool, it was unique and I have never seen any other play wear the same name.
And there you have it, the history of my gamer names.