Since mine is so different from the rest on here, figured I'd post.
Long story short, here goes:
When a teenager, found myself on a MUD (text based multi user dungeon game) and created a name that worked for the game called Methyx (meh-thex) a mythical conjurer (magic user).
Then later I joined up on the game World of Warcraft with my kid, and recreated the character Methyx. Later I had a slew of them all centered around the -thyx theme.
Envithyx (invoke's Magic was my thinking) is my mage and was my main character for a long time.
When I joined and it asked for a handle, I went duh... um... ok I'll use this one not even thinking about the content or theme.
Hence, I'm Envithyx. Go figure
If I could change it, I probably would.
On the other hand, they called me Envi for short in the game, and on the side, guess that could work given we own CVOs. All negative connotations aside.