Well, I'm most likely going to beat you all in my nerdy nickname origin.
A fair time ago, I used to play role-playing with a group of friends (table-top, not LARPing - I have standards, you know)
The very first role-playing game I ever played was Vampire, the Masquerade. I needed to name my character, a fine, young, somewhat psychotic Gangrel. I called her Sasha, as I have always liked that name.
Not knowing what last name to give her, someone thought the the name sounded rather Russian (or something) and so suggested Densikoff.
We had many great adventures, and became hugely powerful, until someone tried to nick some magic gauntlet or something, and then some even more powerful faerie folk appeared out of nowhere and put a stop to all our fun by ruling that we could only do good now, to make up for all the bad we had done. Or they'd kill us.
This was no fun, and so we stopped the game.
And so, here I am before you as Sasha Densikoff, with not a hint of my real name to be seen anywhere.
Beat that!