I went to Comic-Con with my brother Ed for the very first time last year. One of the best moments was when I saw Simon Legno (the creator of tokidoki — http://www.tokidoki.it/). I bought the vinyl toy he is holding (Mozzarella) and had him sign it!
If you look closely, you will see that he is wearing a Hello Kitty/tokidoki necklace.
I checked out his site later and saw this in the Collaboration section: