It's hard to tell from the picture, but it's on this lovely grayish-blue paper.
I actually took some care with trapping on this one, and it turned out pretty good. There's a little bit of fill-in of light brown where there shouldn't be, but no dead space between the light and dark brown. _tove and aleffert came along, and the former made a T-shirt with some brie-protocol in-joke on it. It came out nice, too!