I have taken up the challenge and my sketchbook arrived in the mail this past week. I chose the subject dirigibles and submersibles, don't ask me why, it just appealed to me for some reason. Now I have to start actually thinking about what I will do. Not sure if I will replace the paper with something more substantial like some others have done, or just use appropriate media. Thought it would be a fun idea. I'll post some of the work after I get started.