I'd love to see someone build an IDE that lives locally but syncs up to a cloud service so I can pull everything back down to a different machine and work there. I think you could actually do this with Docker, where your "IDE" would not be an editor, but a virtual system with the code, the database, a web server, the right version of Python/Ruby/foo, dependencies, etc., and you could use whatever editor you wanted. As you worked, the app would use Docker to save the state of the world and push it up to the server. It seems like this would get the benefits of cloud IDEs but still provide the low latency and flexibility of working locally. I don't have the time or expertise to build it, but I hope someone will!