I am (in 'real life') known by six variations of my forename - different people from different times in my life call me slightly different things and always have. I conceived my username on a Saturday, so I became Day6, (I was going to call myself SaturdayGran but it was a bit much to type!) - and I have been asked if it's a biblical reference too!
I wish I had introduced myself to OH by one of the shortened forms of my name, but I gave him my full moniker when I met him, which I am not fond of, and he uses it. 