I just received my add-ons development t-shirt! The t-shirt is so cool! It features the Gran Paradiso robot, which has become the official character for Firefox 3. It's a gift sent out to the developers which had at least one Firefox extension compatible with Firefox 3. I received this for my Find In Numbers extension. You may want to try the extension by the way.
Here is a picture from the front and back of the t-shirt:
I'm quite excited!
Also, I just found out that there is a plan to actually build the robot from cardboard in Dolores Park, San Francisco. I won't be able to take part in this event myself, but I can't wait to see pictures (and movies) from the built robot!