I always carry around a little pen and notebook in my back pocket, handy for jotting down lists, reminders, and ruminations. My latest little book is gridded. I heart grid/graph paper.* Why? I don't know—countless reasons. One, recently discovered, is that it's excellent for making rectilinear Art Naïf streetscapes like this one:
Do you have any comparable stationary/office supply fetishes? (Or am out on an obsessive-compulsive limb with this one?)
* I also heart gridded index cards. I can only find them at the big box office supply store, but it's worth the trip for my extra special 3 x 5 grid-fix.