Wow, good stories in here.
Mine is a two-parter too. My last name has the "Duke" sound in it so; like my father before me, I'm called the Duke, or Duke. This happens especially when there are more than one "Mark's" in the room with me. My initials spell out MAD so one day my boss called me "Maddog". I decided to put the two names together to become Duke Maddog. My avatar was created by my wife who took a mad-looking puppy; photochopped in a sword, cape and crown (she also added the "M" to the cape) and sized it just right for an avatar for me.
There's my story.
Kewl!