Basically, on the once notorious sheppard_n_weir, there was the "omg, whyfore it be called Sparky" FAQ and Liz (no, not that liz, the other liz. No, not that liz... never mind) reported some fandom legends about how it got started (involving the Electric Chemistry of the actors, natch*, but more interestingly, how apparently it was used in a fanfic and Just Caught On).
*natch = naturally, but cooler. Someone asked me that yesterday.
With great care and historical accuracy, that portion of this mythical fanfic has been reconstructed FOR YOU:
"Major Sheppard, seriously, WHY is everyone giggling at us?"
John shrugged. It was sort of starting to get on his nerves. "I have no idea. Ever since you asked me to help you find a way to plug in that desk lamp in your office..."
"Well, that WAS pretty funny." Elizabeth smirked, because she was evil.
"How was I supposed to know it would practically electrocute me!?"
"You need an adapter to go to England, John. I'm pretty sure that just jamming a 120-volt plug into a slightly plug-shaped hole on an Atlantis wall was not the best course of action."
"You say that NOW."
"I said it THEN."
She had, actually, but he glared at her anyway. After all, it was her desk lamp, and she wasn't the one who had to go around for two days smelling like toast.
"Besides, I don't think they're just laughing at you, John," she said, probably to lull him into a false sense of security. "Lieutenant Satterfield and Doctor Fitzroy were talking in the mess this morning, and they went silent when I walked in. Satterfield actually ran out of the room."
But then, Satterfield was a heck of a weird kid.
"I don't know," Elizabeth said, waving a hand. "I guess it's good that there's a rumor mill. It will make Atlantis feel more like home."
While John agreed with her, morale-wise, he'd really appreciate it if he were let in on the joke. And, if the snippet he'd overheard while walking past the infirmary the day before about what Doctor Weir and Major Sheppard might *really* have been doing to "make sparks fly" (and knock out all the power to the control tower too, oops).... well, if that was the rumor, he'd be a lot less annoyed if it were actually true.
"I'll fix it," he told Elizabeth. There was probably a regulation somewhere about not speculating on your superiors' sex lives -- or lack of same -- right? There totally had to be.
"I don't care about that," she said. "As for the other thing, Rodney said he'll fix my lamp -- and the, uh, black spot on my office wall."
Wasn't that sort of work typically "below" Doctor McKay? "That's awfully nice of him."
"Oh, it's not out of the goodness of his heart. I gave him something in return."
He didn't like the way she was looking at him. Not at all. She couldn't possibly have *actually* done something with Doctor McKay, could she have? No...
"What?" he asked, and his voice squeaked a little damningly.
Doctor Weir practically chirped: "I told him he could call you Sparky for the rest of the mission."
And that, ladies and gentlemen, is how rumors get started.