GitLab Web IDE
Wow, very cool. Lots of new players in this space: https://repl.it, https://glitch.me, and now GitLab (and I'd be surprised if GitHub doesn't follow in tow).Cloud9's acquisition really left a big hole in the market. AFAIK there's still nothing out there that gives you a decent code editor (edit multiple files, have multiple tabs open, etc) that also gives you access to a Linux shell and ability to expose ports like Cloud9 did.Personally I'm most optimistic for https://repl.it. They already have a core userbase in high school classrooms and have been adding a ton of support for serverside applications to make it more appealing outside of the classroom.