Once, everyone in the group started wearong silver rings, because they local jewler had a surplus pf them we bought up for easy wealth transport.  He then asked us if we were using them as identification of our group, and it struck us as a good idea, so the Silver Band was born.  
Later, in a Realms game, we ended up fighting a werewolf priest of Malar, and none of us had silver weapons, all we had was my sun elfs holy symbol of Corellon, a silver crescent moon, so teh party rogue ended up stabbing teh werewolf to death with it.  I named us the Company of teh Crescent Blade after that, best I could come up with, I tried translating it into elven (most of us were elves) and the best I could get was Sha-Teu'Vel (friends of the moon blade)
He still wears the slightly notched and bent out of shape holy symbol as is 
Usually we just cant come up with anything that sounds good, and wed rather have no name at all then a bad one.