My call sign originated from Runescape (like DoubleWolf). 6 years ago I was known as Blue Falco12. I came up with that name from a mixture of my favorite color and StarFox on the Nintendo 64. Blue Falcon was taken so I had to settle with the next best thing.
I later decided to change it, but couldn't figure out to what. At that time my favorite band was Mudvayne and prophet sounded very cool. I use MudvayneProphet for most of my usernames online. My Xbox Live gamertag has since been changed to Prophet MVG due to the fact that I joined a team and they paid me to change it.
Once in a while I'll still listen to Mudvayne, but I've become less genre specific when it comes to music. I pretty much listen to it all now.
People generally refer to me as Mud, Mudvayne, Chris, One of The Chris', or Action. Action came from my training with some friends at LCSD. My last name is Acton, but they misspelled my name tape and it said "Action." It hasn't really bothered me and is actually kind of cool. Friends at the department call me Officer Action. Plus it sounds really funny when a drunk is trying to say it.
If my call sign wasn't attached to me I would probably change it to Officer Action.