Drupal participated for the second year in the Google Summer of Code. This is a way for open source projects to earn some cash, to get new participants, as well as get some code done.
This year, Drupal decided that two mentors will be assigned per student, while Google would only recognize one mentor as the official mentor. According the these rules, I was not supposed to get a T-shirt since Owen Barton was the official mentor for Wolfgang Ziegler.
Well, as a pleasant surprise, a FedEx package turned up with a T-shirt in it. Totally unexpected. This year the T-shirt is black with orange and yellow.
Here is last year's T-shirt.
Here is a photo of the relevant part of the T-shirt. The only other marking on it is a small Google logo in white on the upper back.