i had a small mirror (the kind you might see in pubs / bars) in my room with the text "campari" written on it.
just staring into a blank field on my screen, which was waiting for me to type in a nickname, i used "ari" from there on and it grew on me.
after some time i decided that i wanted to change it, to maybe sound more soothing, to be more of a real full name and be longer (not just 3 letters), in order to make it easy for people to still spot me i therefore named me ari_elle....
up to this date many call me ari ;-)