The precious.
HEY! I’m Shecky. 
Oh, and I’d be Trouty.
Vanity search complete.
Kitty!! (with both exclamation points)
“Who?”
I liked him before, but that’s just badass.
Me? I think I’d ask for the code name Dark Knight.
They’d call me “Saysd’ohalot.”
Vajayjay. Just because I’d love hearing secret service goons muttering it into their walkie talkies.
“Omniscient is on the move!!”
“Who?”
"…sigh…Turd Ferguson is on the move. "
“That’s right.”
I’d probably get something like “Crosshair” or “Target.”
Well done.
Peckerhead.
Slacker.
I would want mine to fit a key requirement of being secretive:
Nastyshag.
High-Value-but-we’ve-got-coupons.
Boom Boom.
I don’t think it’s purpose is so that no one knows what they’re talking about - they’d have to change it pretty frequently then to keep it secret, which would just lead to confusion. It’s purpose is to have an unambiguous shorthand.
What do you mean if ? I play RPG’s & my secret service codename is Upfront Madison
Probably Poofter. I would hate it.
**Giggles. **It’s my Hash name. I hate it.
Assassin. Keep them on their toes, that’s the idea.