I bought a Supernote recently as a note-taking device, and that's worked out really well. It's almost like pen on paper to write on, but I can open new documents freely to make notes in, then consolidate them later because they're all already in one place. The stuff that's just working out or temporary diagrams I can delete later, and the rest I can archive.

On the other hand, I have gone from having a clutter of paper on my desk to having a clutter of notes on my Supernote, so maybe I've just moved the clutter from one place to another. But at least it's now less visible!