I was choosing a username for Runescape (way back in '05), and was brainstorming something besides "Skulldeath######."
I'd heard the name "Thor" somewhere or other (an RPG randomized name, I think), and thought it was pretty cool. At the time I was completely
oblivious to its importance in Norse mythology so I was getting pissed off that all the names with "Thor" in them were taken, and I couldn't understand why. So, I started using various suffixes that weren't numbers. Coincidentally, I have a periodic table next to my desk, and the first word I saw as I looked around was "gold."
Thus, "Thorgold" and variations thereof has become my handle for pretty much eveything. Hell, it's even my paintall callsign
...though even THIS name I've found to be in use elsewhere, lord knows how.