My first nickname was Mark the Great (yes I know what you are thinking, at those times I was really impressed by Alexander the Great >.> ). When I played Might and Magic VI for the first time one of the characters was named Marcus and I liked that name so much that I wanted to use it too.
When COH1 came out I called myself Marco2389 (2389 stands for 2nd March 1989, my birthday). I was eventually forced to create a new one for a silly reason: when I bought COH

pposing Fronts one of my friends wanted to try the campaign and I gave him my copy. When Relic recognized there were 2 accounts with the same CD-key they asked both me and the other guy who was the owner of the copy and he stupidly pressed the "I'm the owner" button, getting my account suspended.
Since I had the real/physical copy of the game I was able to convalidate it by putting the DVD inside the PC and I was able to create a new account. (Thanks to Relic support)
My plan was to name myself [RA]Marcus2389 but since [ ] were not accepted I ended up creating what is still considered one of the worst looking accounts of the whole COH1 history: XxRAxXMarcus2389 (where XxRAxX was the tag xD)
Today I'm just Marcus2389 ^^