Back in the day, I worked in an office with some friends, and there happened to be 2 too many Jasons. Someone would walk in and say "Hey, Jason" and 3 of us would turn around. To avoid confusion, they started calling me Mason Jaxwell, which is my full name, Jason Maxwell, with the initials reversed. We always thought that making a person's first name possessive (adding an "s") can result in hilarity (Eg: Kevin's Bacon). I hit a character limit trying to register masonsjaxwell somewhere, and so masonsjax was born, and has been my handle everywhere ever since. Fascinating story, I know.
I'll pick an avatar when I finally cough up the funds for a paid account here.