Check out TiddlyWiki http://tiddlywiki.com - it's an open source program that's been around for 15 years. TiddlyWiki wraps up a bunch of web-type resources (text, images, pages, etc.) into a single JavaScript file that works on anything that can run a browser, and can be run straight from a file, or integrated with a variety of web backends. It's actually one of the most interesting pieces of software I've seen in the past 20 years, predating many of the capabilities of iPython/Jupyter notebooks, although aimed at different use cases. That said, although I have some TiddlyWiki notebooks, I find that OneNote is my primary go-to notetaking choice these days, at least partly b/c I have a Surface and taking notes with the pen (both text and sketches) while still having the ability to use pretty good handwriting recognition is really my killer app.