In the past, developers have resorted to using screen-sharing and IM tools to work on their programming projects. These could be frustrating, since you can't really jointly write code very easily. The new Cloud9 IDE facility lets multiple developers concurrently edit code, since the entire runtime environment is available to everyone simultaneously, similar to how multiple authors can edit a Google Doc together.

Developers on Cloud9 can now give others real-time collaborative access simply by handing them their project links. For an open source project, any person opening a link will gain access without delay. For private projects, the viewer gains access immediately after acquiring the project owner's permission.

Cloud9 IDE incorporates HTML5, and supports Python, Ruby and PHP. There are both free and $15 monthly plans available, the latter for private projects and runtime environments. It will be available October 1.