I rarely use paper notes any more, but I still value the immediacy and minimized distraction of paper, and I simulate it by using the most simple editor, Notepad. I use it with a fixed width of 66 characters which preserves the impression of a paper that lies next to my reading, and I even have a file called 66.txt to repair the width if it was lost. Notepad also serves me to inspect other file formats by dropping file icons on its app shortcut.
For more about paper legacy, see Single page.