Hee! I would have shipped Krycek with anything that moved. I did like a bit of Mulder/Scully--the twisty ones that didn't gloss over how screwed up they both were, especially Mulder--but my heart always belonged to Nick Lea's Krycek. I'm still bitter about his death, damn it!
You're probably right about the Snape connection, because there certainly are similarities between them, aren't there? Double and triple agents, uncertain loyalties, hated by both sides, unfair and unworthy deaths... and of course, they're both sexy bastards who look good in black.
The X-Files fandom was very different, wasn't it? I seemed to spend all my time on archives, because they were massive and usually well-maintained. "Exigency" sounds awfully familiar to me; I wonder if I'd remember it if I took a quick glance at it. I haven't really read X-Files fic in so long... ~is tempted~