Always, for everything at work. Reach over, pick up notebook, write, done. No boot time, no drop down menus, no learning/adhering to someone else's way of doing things, no end-of-life versions, no stylus driver issues, _NO BUGS_. A5 size pretty much any brand that's immediately available when I need a new one. Lined, not dot and not graph. I'm very visual-oriented and am always rendering thoughts, processes, algorithms, etc. as a _diagram_. I've found nothing digital even comes close to pen/pencil and paper. To digitize and share I take pictures of my drawings. Meeting notes, discussion summaries, decisions (and who made them) all dated. Hugely important when I have to remember histories of events, etc.