'see, back in 1985, I got involved with working the bar at SpoKon '85, the Spokane science fiction convention, and this ended up with me being on the con committee at SpoKon '86. I elected to go as Elric of Melnibone, complete with a hand-made oak bokuto Stormbringer as tall as I am.
Being on the con committee meant I was hanging out with several of the guests, in particular the artist GoH, Dameon Willich. (A name known to any aficionado of cardboard crack.) This in turn led to me getting involved with a group of Seattle-area LARPers that Dameon ran.
Now, it seemed presumptuous to keep on using the name Elric on a permanent basis for LARPing. But, having gotten to know a fair chunk of these people as Elric, I didn't want to change the persona too much. I was sitting pondering this one day, when out of the blue, the name Alaric popped into my head. So I sat down and created the background for the character, gradually getting more pieces of it together over time.
Fast-forward to 1989, and the creation of alt.callahans on usenet. My generated-by-my-employer's-rules email address was an unpronounceable mishmash that looked like the designation of some new virus out of Darkest Africa, and Callahans is one of those rather-less-than-real places anyway, so I started using Alaric as my nick and persona in a.c.
By the time I discovered ICB in 1993 or so, there were probably fifty people worldwide who knew me as Alaric for every one who knew me by my real name, and also by that time I answered to Alaric faster and more automatically than I did to my legal name anyway. 1993 was also about the time I started using linux, and pretty much ever since then, every time I've been able to pick my own account name I've used alaric. (I haven't yet got Red Hat to alias it for me, but I know the IS guys, and I'm working on it.)