That's a tricky question since I'm not really a fandom person... I don't write fanfiction (too difficult) or really do anything "fannish". Which means I never went through the god-awful fanfic stage. I did write some god-awful original fic, though...

Still, my first and probably only real fandom? PETZ. And I still play the games sometimes too and make breeds because IT WILL NOT DIE IN MY HEAD. The creepy thing is how many internet people I ran into who remember it.