Microsoft has quietly rolled out a SkyDrive cloud development feature. If you create a text file on your local PC and upload it to SkyDrive, you can open the file in SkyDrive and edit it in place with a full set of code editing tools.
It recognizes a number of programming languages, including JavaScript, CSS, HTML, C#, Ruby, PHP, Python, SQL cmd files and more. For these it offers tab completion. In addition, it has features like search and replace, as well as some collaboration and syncing capabilities.