Useful for avoiding annoying, endless repeated attempts by the asker to 'get the name right', or avoiding the inevitable "So where are you from? ...So where are you *really* from?" questions.
Almost always only a syllable or two, and easy to shout in someone's ear when the music is loud.
Often a middle name or something that the person doesn't normally go by.
"Hey man, I'm Zee, nice to meet you" -Bar name of Zaid