Larry isn't my real name, but in high school there was one kid who insisted on calling me Larry for the whole 6 years. No real reason, apart from the fact that my last name is Long and it sounded good to him. Then, once I finished school and went to University, a different guy started doing it out of the blue, for similar reasons, and a few others took it up. We formed a basketball team in our Uni days with a rule that your team mates got to choose the name that went on the back of your singlet, and my mates put Larry on the back of mine. Larry isn't a common name at all here in Australia - in fact it is probably seen as a funny American name that you don't see anywhere, so I thought it made for a good nickname and started using it for everything online.