Personally, I would rather see a Polo with a "generic" Axiom logo on it, with individual name tags being worn as "name tag stickers" for the day.
I just re-read this whole thread, and realized that I wasn't very clear in my above post.
What I was thinking was an Axiom logo, specifically altered to commerate the 30 years, the day, or the forum, but without peoples' actual names/screennames on the shirt.... identifying people that day could be done with some sort of a name tag for use on that day only instead of permanantly being a part of the shirt.
It still may not be the preferred idea, but I wanted to make sure I was clear in that my post above just said "generic Axiom logo". I meant a common (among each shirt), user-designed logo. This should also lower the overall cost since each shirt doesn't need to be embroidered for each name.