Okay, so I checked around the different forums and found topics like, "What did you call yourself in FR/LG?", however there are none like that for GSC (At least, none that I could find. Trust me, I just spent like 20 minutes making sure I wasn't repeating a topic. If I am, then somebody just lock this, and my bad!).

So, now I ask you, the reader, to let loose and reveal what you have dubbed yourself any games from the Johto age! (Sorry, just thought that sounded cool...)

Myself? Well, I completely change the names in Gold and Silver every time I reset the games, but I always play Crystal as a girl named (drumroll...) Crystal!

I think I called myself by the default names but I probs chose ALEX.

Gold: TAYLOR; Kenji
Silver: Reiji
Crystal: Skye

Gold ones - TAYLOR was the one I called myself when I was a total Pokemon n00b in third or so grade. Kenji... meh, can't remember why I named myself that.
Silver one - Reiji is the Crow Zoanthrope and is utterly cool. 'Nuff said.
Crystal one - w00t for my nickname.

Well, my Gold is corrupt, so here are the many names I used in a desperate attempt to get my sacred game working.

BOB, SATOSHI (dont ask...), Satoshi, GOLD, Gold, OMGWORK (yes...that WAS what I called myself), IGIVEUP, WORKPLZ (this was the last of them)

-Gardevoir~

I call myself Michael because that's my name

The first name I gave myself was something like ASH .... hard to remember but I hate that name now ,lol .
I lost my Silver Version so I can't remember my what I named myself...

I'm unoriginal, so:

Silver: SILVER, Rival GOLD
Gold: GOLD, Rival SILVER

I tend to name the main character after the game's colour, works for me so meh

i play a girl in crystal. my name is in real life Giles=>female form of Giles is Jill, so I am Jill on crystal

Ash, like from the Anime show!

In crystal (playing as I type). Nik

My latest name is Hyperus. I wanted it to be Hesperus, which means "evening star," but it wouldn't fit. So I contracted it into Hyperus.

I called my self Archie.

Sean. I dunno, it sounds cool to me. BUT ITS NOT MY REAL NAME! I will not say my real name lol...

i call my self gold in gold and silver in silver and guess what? i call m self crystal in crystal

With me, my username.

i called me KRIS

I called myself David, my real name.

Lol, no originality

I always in everygame name myself one of 3 things. Austin,Auzzie or Auz, and I have 3 distinct defferent names because I always use them on different games in each generation.
It goes:
G-Auzzie
S-Auz
C-Austin
I always use my real name on the third of the generation, like Yellow and Crystal and Emerald. Then I use Auzzie on my first opened game and Auz on my second, I opened Gold first because I thought Ho-oH looked kool.

i have a vague recolection f being named fluffernutter but i could be mistaken

My Gold name was Hiro for some odd reason..... I think I was trying to make it Hero, but made a typo and didn't realize it. And stranger still, my rival's name was always ???. Weird, huh?

Also, the rival was named Gary.

Every time I have to start a new game on my Gold (my file is corrupt ) I name myself MyFOOT! because I say it all the time in real life >_<.

I started a new file and called myself HAYWOOD (as in Haywood Jablowmee) and I called my rival DICK...because that's definitely how that guy acts.

In RBY when I restarted once I named myself you moron...and Oak said something like "Hey, you moron! Don't go out in the tall grass yet!"

Brian
Tyler
Silver

John in all games. It's not my real name though.