If you call me Michael, you're an actual friend of mine or someone who pays close attention to introductions.
If you call me Mike, you're either my Mom, my oldest friend Gami, an editor friend named John, or another Michael who also always goes by Michael but who found that the two of us had no problem calling each other Mike. If you're not one of those people, you're way clueless, as I've probably already told you a dozen times that I go by Michael and not Mike. Or you're assuming a familiarity which does not exist, and probably won't, given your insistence on calling me Mike.
If you call me MAB, you're a student who asked once if I would answer to that, and I said sure.
If you call me Mabfan, you're someone who is confusing my URL or my LJ handle for my name.
I can't think of any other interesting ones at the moment, although this whole thing reminds me of a scene from the second season of Star Trek: The Next Generation. Dr. Pulaski calls Data (DAYTA) by the pronounciation DATA (short a in the middle). When he corrects her, she asks what the difference is. He responds:
"One is my name. The other is not."