I was recruited by etc. (whose nom I finally learned, so I can give her proper credit!). I'd heard vaguely of the NPL for some years due to articles in GAMES and whatnot, but it was a conversation backstage during rehearsals for a Gilbert & Sullivan production that we were doing together that she pointed me in the right direction.
Also Siri and Spellbound. I can also take some credit for Wesley and Arcs, through the Mystery Hunt.
My nom doesn't have much of a story behind it, except that I thought “saxifrage” was a nifty word that people really ought to hear more of. (It's a small flowering herb.) In one version I have of the Victorian-era language of flowers, it represents “affection,” which is rather nice. And it derives from a Latin root meaning “rock-breaking,” which is rather evocative. (Of what, I'm not sure…) Mostly, though, I just liked it.