I'd love to see a notebook environment that could somehow combine Python data science tools with DOM/JavaScript interactive visualization tools like D3. Jupyter and crew do former and this does the latter. What we really want is both. Would obviously be tricky to both implement technically and to design a good experience that lets you swap between the two languages and paradigms. Like you might have run webserver behind the scenes to expose the Python produced data to the D3? Stuff like that. Sounds like an interesting challenge. Because I'm generous though, I'd like to give this idea away for free to anyone willing to execute on it. Just joking! Devil in the details. More accurately, I'd just be pumped if someone had the energy to tackle this beast. Also, I'd definitely pay for a hybrid tool like this.