Sign language from the world of Haibane Renmei

This wonderful Haibane Renmei website even includes a written alphabet and pictures of the sign language system used by the Tooga, the mysterious masked people who are the only ones allowed to speak to traders from outside the Wall of the town. The downloads section includes the font used in books in the town. Yes, this is the level of detail found in this anime series. Nifty, eh?