My first two initials are SP.
I used to have something of a gambling habit.
One day I walked into work and picked up my clocking-in card - a comedian had crossed my first two names out and written 'StartingPrice' in their place (the management had a barny, at me at first, until I explained that I didn't do it myself, and had no knowledge of it, and then at the workforce in general, as they couldn't find the culprit).
But it stuck as my nickname, that, or just SP