You will need to edit your user.cfg file.
This is located in the var folder ( C:\\Documents and Settings/your_username/Application Data/Armagetron/var )
Now open the file called user.cfg. Scroll down quite a ways untill you see: PLAYER_1 yourname
This is where you put the funky letters (most of the ansi characters work for this).
Save the file and open Armagetron. Now your name is pimped out

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P.S. If some of the symbols don't work, try using the ones from
here. I'm pretty sure that all the ones that I put on there work in game, if not, then about 99%

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