My first ever screen name was JerJerrod, after
this dude from Return of the Jedi who greeted Vader to the Death Star. I only used it a little bit as I didn't use the internet much then. I later used the last names of two characters that I had drawn and used in a (crappy) short story; first the villain's, who died in it, then the hero's, which has now actually become my last name.
That lasted until almost 5 years ago when I realised I was a girl, whereupon I then decided to use my screen name to test out girl names on myself, to see how well I would identify with them. I quickly latched onto Oriet, which was a middle/last name of a great aunt (I think; the relation might have been a little more distant, and it might have been spelt Oreit), and I found very quickly that I love it, and it has become my middle name (I always liked the idea of being called by my middle name by friends, but didn't like my birth name). I've also used MadamOriet as a variant of it.
I've also used sanjahime, which is what I finally decided on as my first name appended with the Japanese word for princess (I was/am such a weeaboo), though interestingly if the 'j' is not pronounced like a 'y' (as the name is German) it actually means "three shrine princess", such as from
Sanja Matsuri.
The other one that I've used is Robyn Locksley, the name I used for a hunter in the game Ragnarok Online. As should be obvious it's a feminisation of Robin of Locksley, better known as Robin Hood, which I found appropriate since hunters use bows and arrows.