I've pretty much abandoned all my other sketchbooks and have started on a new one. This one is my Cupertino sketchbook. Its mostly of studies I've found off the internet and coworkers in meetings. There is one big difference in this sketchbook from my others though. I'm going to draw in it entirely in pen or more specifically ballpoint pen. I've always used a pencil as a crutch so as not to make any mistakes. But I'm taking a baby step and drawing all my new stuff in pen now.