This is a very hard one for me, as I use a lot so I'll go through them:
Online FPS: The Undoer
Casual Online (to friends): Issy
Dwarf Male: Elrok Ironrend
Elf Female: Isune/Ashunor (Windblossom)
Human Male: Elus
Human Female: Rideia Estelma
Dwarf Female: Grena Ironrend
I've never really touched futuristic games, but I'd probably just use Elus.
The truth of the matter is, I always go Dwarf Male, I love dwarves and when I played World of Warcraft I roleplayed a character named "Elrok Ironrend" and to this day, I still regret joining a raiding guild and leaving my Roleplaying buddies. Elrok is sort of, the embodiment of what I wish to be. Grena was his mother, she had a nice beard, nice and thick... *nostalgia*.
So if you ever see Elrok Ironrend, it's almost certainly me, and definately if he's trying to shake some poor bloke down for his coin.
The Undoer on the otherhand? Also always me. You have been, undone!
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All my characters are really named after my WoW characters, before that I could myself a rubbish name which I sharn't say for fear of letting people know. (It was sirfragsalot, joke). Even Izoon, my name here, is based on Isune (evolved from Elune/Azhune and then devolved backwards into Ashunor for when Isune was taken). The only recent name I've been by was on Morrowind as "Erildite" playing a Dark Elf male, which as you can see above I don't have a name for, upon realising how much that sounded like Arildite (A form of glue) I wanted to eat my own hand, and stopped playing male elves.
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Final note: This post made me cry a bit about Elrok and Isune
