I feel that it's important that each person have them, for a sense of identity, for good mental health, or what have you. Mine are:
MC Amon-Ra
DJ Sizzling Pig
But who knows whether I'll stick with them. DJ Sizzling Pig is a bit silly. So go on, what are your awesome appellations?
PS: For those who don't know, an MC is, in this case, a Microphone Controller, ie. someone who... controls the microphone. A DJ is a Disc Jockey, like those nice people on the radio.
PPS: MC names can also be arranged so that the MC part comes after the name itself. For instance, off the top of my head, there is Forthright MC on Grand Theft Auto: San Andreas. He's insane.