I'll try to make the actual story of the screen name short: when I first got on the internet in 1998, I used to sign on in places as Arglebargle IV. If you read Harvard Lampoon's "Bored of the Rings", this was in a footnote early on about a king: "Either Arglebargle IV or somebody else". I'd read the book in 1970 but always remembered this, so I used it as a screen name. But everyone and their sisters asked for explanations, which I very quickly got tired of giving, so I shortened it to Argh.
I'm sorry there's no more gruesome, sado-masochistic reason behind this, Miss Ruth. If I ever get time, maybe I can make up something really juicy for you!
Cool explanation re: your screen name though. Mine is soooo dreary and unoriginal!